Properties of the international symbols

Burzlaff, H.; Zimmermann, H.

doi:10.1107/97809553602060000526

International
Tables for
Crystallography
Volume A
Space-group symmetry
Edited by Th. Hahn

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International Tables for Crystallography (2006). Vol. A. ch. 12.3, pp. 823-832
https://doi.org/10.1107/97809553602060000526

Chapter 12.3. Properties of the international symbols

H. Burzlaff^a and H. Zimmermann^b ^*

^a Universität Erlangen–Nürnberg, Robert-Koch-Strasse 4a, D-91080 Uttenreuth, Germany, and ^bInstitut für Angewandte Physik, Lehrstuhl für Kristallographie und Strukturphysik, Universität Erlangen–Nürnberg, Bismarckstrasse 10, D-91054 Erlangen, Germany
Correspondence e-mail: helmuth.zimmermann@krist.uni-erlangen.de

The standard Schoenflies, Shubnikov and short and full international space-group symbols used in the present edition and the 1935 edition of International Tables are extensively tabulated. Examples are given of how to derive the space group from the short international symbol and how to derive the full symbol from the short symbol. The derivation of symmetry elements that are not given explicitly in the full symbol is described. Standardization rules for the short symbols are given, and systematic absences and generalized symmetry (e.g. colour groups) are briefly discussed.

Keywords: space-group symbols; international space-group symbols; generators; symmetry operations; general position; Hermann–Mauguin symbols; Shubnikov symbols; Schoenflies symbols; systematic absences.

12.3.1. Derivation of the space group from the short symbol

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Because the short international symbol contains a set of generators, it is possible to deduce the space group from it. With the same distinction between generators and indicators as for point groups, the modified point-group symbol directly gives the rotation parts W of the generating operations (W, w).

The modified symbols of the generators determine the glide/screw parts $[{\bi w}_{g}]$ of w. To find the location parts $[{\bi w}_{l}]$ of w, it is necessary to inspect the product relations of the group. The deduction of the set of complete generating operations can be summarized in the following rules:

(i) The integral translations are included in the set of generators. If the unit cell has centring points, the centring operations are generators.
(ii) The location parts of the generators can be set to zero except for the two cases noted under (iii) and (iv).
(iii) For non-cubic rotation groups with indicators in the symbol, the location part of the first generator can be set to zero. The location part of the second generator is $[{\bi w}_{l} = (0,0,\!-m/n)]$ ; the intersection parameter is derived from the indicator $[n_{m}]$ in the [001] direction [cf. example (3) below].
(iv) For cubic rotation groups, the location part of the threefold rotation can be set to zero. For space groups related to the point group 23, the location part of the twofold rotation is $[{\bi w}_{l} = (-m/n,0,0)]$ derived from the symbol $[n_{m}]$ of the twofold operation itself. For space groups related to the point group 432, the location part of the twofold generating rotation is $[w_{l} = (-m/n,m/n,m/n)]$ derived from the indicator $[n_{m}]$ in the [001] direction [cf. examples (4) and (5) below].

The origin that is selected by these rules is called `origin of the symbol' (Burzlaff & Zimmermann, 1980 ). It is evident that the reference to the origin of the symbol allows a very short and unique notation of all desirable origins by appending a matrix $[{\bi q} = \langle q^{1},q^{2},q^{3} \rangle]$ to the short space-group symbol. The shift of origin can be performed easily, for only the translation parts have to be changed. The new matrix of the translation part can be obtained by $[{\bi w}' = {\bi w} + ({\bi W} - {\bi I}) \cdot {\bi q}.]$ Applications can be found in Burzlaff & Zimmermann (2002 ).

Examples: Deduction of the generating operations from the short symbol

Some examples for the use of these rules are now described in detail. It is convenient to describe the symmetry operation (W, w) by a pair of row matrices. The first one consists of the coordinates of a point in general position after the application of W on $[\pmatrix{x\cr y\cr z\cr}]$ ; the second represents the translation part $[\pmatrix{w^{1}\cr w^{2}\cr w^{3}\cr}]$ . In the following, both are written as a row. The sum of both matrices is tabulated as general position in the space-group tables (in some cases a shift of origin is necessary). If preference is given to full matrix notation, Table 11.2.2.1 may be used. The following examples contain, besides the description of the symmetry operations, references to the numbering of the general positions in the space-group tables of this volume; cf. Sections 2.2.9 and 2.2.11 . Centring translations are written after the numbers, if necessary.

(1) $[Pccm = D_{2h}^{3}\ (49)]$

Besides the integral translations, the generators, as given in the symbol, are according to rule (ii): $[\eqalign{&\hbox{glide reflection} \quad c_{[100]} \ : \ (\overline{x}yz,00\textstyle{1\over 2})\ \ (8)\ \cr&\hbox{glide reflection} \quad c_{[010]} \ : \ (x\overline{y}z,00\textstyle{1\over 2})\ \ (7)\ \cr &\hbox{reflection} \phantom{glide ion} \!m_{[001]} {\hbox to 2.75pt{}}: \ (xy\overline{z},000){\hbox to 7pt{}}(6).}]$ No shift of origin is necessary. The extended symbol is $[Pccm \langle 000 \rangle]$ .
(2) $[Ibam = D_{2h}^{26}\ (72)]$

According to rule (i), the I centring is an additional generating translation. Thus, the generators are: $[\let\normalbaselines\relax\openup3pt\matrix{I \hbox{ centring}\hfill &: (xyz,\textstyle{1\over 2} \textstyle{1\over 2} \textstyle{1\over 2})\hfill & (1)+(\textstyle{1\over 2} \textstyle{1\over 2} \textstyle{1\over 2})\cr \hbox{glide reflection } b_{[100]}\hfill &: (\overline{x}yz,0 \textstyle{1\over 2} 0)\hfill &(8)\hfill \cr \hbox{glide reflection } a_{[010]}\hfill &: (x\overline{y}z,\textstyle{1\over 2} 00) \hfill &(7)\hfill \cr \hbox{reflection } \phantom{tion\;}\ m_{[001]}\hfill &: (xy\overline{z},000) \hfill &(6).\hfill}]$ To obtain the tabulated general position, a shift of origin by $[(-{\textstyle{1\over 4}},\! -{\textstyle{1\over 4}}, 0)]$ is necessary, the extended symbol is $[Ibam \langle - \textstyle{1\over 4} - \textstyle{1\over 4} 0 \rangle]$ .
(3) $[P4_{1}2_{1}2 = D_{4}^{4}\ (92)]$

Apart from the translations, the generating elements are: $[\!\eqalign{&\hbox{screw rotation } 2_{1} \hbox{ in } [100]: (x\overline{y}{\hbox to .5pt{}}\overline{z},\textstyle{1\over 2} 00) \quad (6)\cr &\hbox{rotation } \phantom{\ screw} 2\ \hbox{ in } [1\overline{1}0]{\hbox to .5pt{}}: (\overline{y}{\hbox to 1pt{}}\overline{x}{\hbox to 1pt{}}\overline{z},00{\textstyle{1\over 4}}) {\hbox to 11.5pt{}} (8).}]$

According to rule (iii), the location part of the first generator, referring to the secondary set of symmetry direction, is equal to zero. For the second generator, the screw part is equal to zero. The location part is $[(0,0,\!-\textstyle{1\over 4})]$ .

The extended symbol $[P4_{1}2_{1}2 \langle \textstyle{1\over 4} -\textstyle{1\over 4} -{3\over8} \rangle]$ gives the tabulated setting.
(4) $[P2_{1}3 = T^{4}\ (198)]$

According to rule (iv), the generators are $[\let\normalbaselines\relax\openup3pt\matrix{\hbox{rotation 3 in } [111]\hfill & : (zxy,000) \hfill & (5)\hfill\cr \hbox{screw rotation } 2_{1} \hbox{ in } [001]\hfill &: (\overline{x}{\hbox to .5pt{}}\overline{y}z,\textstyle{1\over 2}0\textstyle{1\over 2}) \hfill &(2).\hfill}]$

Following rule (iv), the location part of the threefold axis must be set to zero. The screw part of the twofold axis in [001] is $[(0,0,\textstyle{1\over 2})]$ , the location part $[{\bi w}_{l}]$ is $[(-\textstyle{1\over 2},0,0) \equiv (\textstyle{1\over 2},0,0)]$ . No origin shift is necessary. The extended symbol is $[P2_{1}3 \langle 000 \rangle]$ .
(5) $[P4_{1}32 = O^{7}\ (213)]$

Besides the integral translations, the generators given by the symbol are: $[\eqalign{&\hbox{rotation 3 in } [111] : (zxy,000) {\hbox to 22.5pt{}} (5)\cr &\hbox{rotation 2 in } [110] : (yx\overline{z},-\textstyle{1\over 4} \textstyle{1\over 4} \textstyle{1\over 4}) \quad\ (13).}]$

The screw part of the twofold axis is zero. According to rule (iv), the location part $[{\bi w}_{l}]$ is $[(-\textstyle{1\over 4},\textstyle{1\over 4},\textstyle{1\over 4})]$ . No origin shift is necessary. The extended symbol is $[P4_{1}32 \langle 000 \rangle]$ .

12.3.2. Derivation of the full symbol from the short symbol

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If the geometrical point of view is again considered, it is possible to derive the full international symbol for a space group. This full symbol can be interpreted as consisting of symmetry elements. It can be generated from the short symbol with the aid of products between symmetry operations. It is possible, however, to derive the glide/screw parts of the elements in the full symbol directly from the glide/screw parts of the short symbol.

The product of operations corresponding to non-parallel glide or mirror planes generates a rotation or screw axis parallel to the intersection line. The screw part of the rotation is equal to the sum of the projections of the glide components of the planes on the axis. The angle between the planes determines the rotation part of the axis. For 90°, we obtain a twofold, for 60° a threefold, for 45° a fourfold and for 30° a sixfold axis.

Example: $[Pbcn = D_{2h}^{14}\ (60)]$

The product of b and c generates a screw axis $[2_{1}]$ in the z direction because the sum of the glide components in the z direction is $[\textstyle{1\over 2}]$ . The product of c and n generates a screw axis $[2_{1}]$ in the x direction and the product between b and n produces a rotation axis 2 in the y direction because the y components for b and n add up to $[1 \equiv 0]$ modulo integers.

Thus, the full symbol is $[P {2_{1} \over b} {2 \over c} {2_{1} \over n}.]$

In most cases, the full symbol is identical with the short symbol; differences between full and short symbols can only occur for space groups corresponding to lattice point groups (holohedries) and to the point group $[m\overline{3}]$ . In all these cases, the short symbol is extended to the full symbol by adding the symbol for the maximal purely rotational subgroup. A special procedure is in use for monoclinic space groups. To indicate the choice of coordinate axes, the full symbol is treated like an orthorhombic symbol, in which the directions without symmetry are indicated by `1', even though they do not correspond to lattice symmetry directions in the monoclinic case.

12.3.3. Non-symbolized symmetry elements

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Certain symmetry elements are not given explicitly in the full symbol because they can easily be derived. They are:

(i) Rotoinversion axes that are not used to indicate the lattice symmetry directions.
(ii) Rotation axes 2 included in the axes 4, $[\overline{4}]$ and 6 and rotation axes 3 included in the axes $[\overline{3}]$ , 6 and $[\overline{6}]$ .
(iii) Additional symmetry elements occurring in space groups with centred unit cells. These types of operation can be deduced from the product of the centring translation (I, g) with a symmetry operation (W, w). The new symmetry operation $[({\bi W},\; {\bi g} + {\bi w})]$ again has W as rotation part but a different glide/screw part if the component of g parallel to the symmetry element corresponding to W is not a lattice vector; cf. Chapter 4.1 .

Example

Space group $[C2/c\ (15)]$ has a twofold axis along b with screw part $[{\bi w}_{g} = (0,0,0)]$ . The translational part of the centring operation is $[{\bi g} = (\textstyle{1\over 2},\textstyle{1\over 2},0)]$ .

An additional axis parallel to b thus has a translation part $[{\bi g} + {\bi w}_{g} = (\textstyle{1\over 2},\textstyle{1\over 2},0)]$ . The component $[(0,\textstyle{1\over 2},0)]$ indicates a screw axis $[2_{1}]$ in the y direction, whereas the component $[(\textstyle{1\over 2},0,0)]$ indicates the location of this axis in $[(\textstyle{1\over 4},y,0)]$ . Similarly, it can be shown that glide plane c combined with the centring gives a glide plane n.

In the same way, in rhombohedral and cubic space groups, a rotation axis 3 is accompanied by screw axes $[3_{1}]$ and $[3_{2}]$ .

In space groups with centred unit cells, the location parts of different symmetry elements may coincide. In $[I\overline{4}2m]$ , for example, the mirror plane m contains simultaneously a non-symbolized glide plane n. The same applies to all mirror planes in Fmmm.
(iv) Symmetry elements with diagonal orientation always occur with different types of glide/screw parts simultaneously. In space group $[P\overline{4}2m]$ the translation vector along a can be decomposed as $[{\bi w} = (1,0,0) = (\textstyle{1\over 2},\textstyle{1\over 2},0) + (\textstyle{1\over 2}, -\textstyle{1\over 2},0) = {\bi w}_{g} + {\bi w}_{l}.]$ The diagonal mirror plane with normal along $[[1\overline{1}0]]$ passing through the origin is accompanied by a parallel glide plane with glide part $[(\textstyle{1\over 2},\textstyle{1\over 2},0)]$ shifted by $[(\textstyle{1\over 4},-\textstyle{1\over 4},0)]$ . The same arguments lead to the occurrence of screw axes $[2_{1}]$ , $[3_{1}]$ and $[3_{2}]$ connected with diagonal rotation axes 2 or 3.
(v) For some investigations connected with klassengleiche subgroups , it is convenient to introduce an extended full space-group symbol that comprises all symmetry elements indicated in (iii) and (iv). The basic concept may be found in papers by Hermann (1929) and in IT (1952). These concepts have been applied by Bertaut (1976) and Zimmermann (1976); cf. Part 4 .

Example

The full symbol of space group Imma (74) is $[I{2_{1} \over m} {2_{1} \over m} {2_{1} \over a}.]$

The I-centring operation introduces additional rotation axes and glide planes for all three sets of lattice symmetry directions. The extended full symbol is $[I{2,2_{1} \over m,n} {2,2_{1} \over m,n} {2,2_{1} \over a,b} \quad \hbox{or} \quad I\openup2pt\matrix{\displaystyle{2_{1} \over m} &\displaystyle{2_{1} \over m} &\displaystyle{2_{1} \over a}\cr \displaystyle{2 \over n} &\displaystyle{2 \over n} &\displaystyle{2 \over b}\cr}.]$ This symbol shows immediately the eight subgroups with a P lattice corresponding to point group mmm: $[Pmma \sim Pmmb,\quad Pnma \sim Pmnb,\quad Pmna \sim Pnmb\quad \hbox{and}\quad Pnna \sim Pnnb.\hfill]$

12.3.4. Standardization rules for short symbols

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The symbols of Bravais lattices and glide planes depend on the choice of basis vectors. As shown in the preceding section, additional translation vectors in centred unit cells produce new symmetry operations with the same rotation but different glide/screw parts. Moreover, it was shown that for diagonal orientations symmetry operations may be represented by different symbols. Thus, different short symbols for the same space group can be derived even if the rules for the selection of the generators and indicators are obeyed.

For the unique designation of a space-group type, a standardization of the short symbol is necessary. Rules for standardization were given first by Hermann (1931) and later in a slightly modified form in IT (1952).

These rules, which are generally followed in the present tables, are given below. Because of the historical development of the symbols (cf. Chapter 12.4 ), some of the present symbols do not obey the rules, whereas others depending on the crystal class need additional rules for them to be uniquely determined. These exceptions and additions are not explicitly mentioned, but may be discovered from Table 12.3.4.1 in which the short symbols are listed for all space groups. A table for all settings may be found in Chapter 4.3 .

Table 12.3.4.1| top | pdf |
Standard space-group symbols

No.	Schönflies symbol	Shubnikov symbol	Symbols of International Tables				Comments^†
			1935 Edition		Present Edition
			Short	Full	Short	Full
1	$[C_{1}^{1}]$	$[(a/b/c)\cdot 1]$	P1	P1	P1	P1
2	$[C_{i}^{1}]$	$[(a/b/c)\cdot \overline{2}]$	$[P\overline{1}]$	$[P\overline{1}]$	$[P\overline{1}]$	$[P\overline{1}]$	$[(a/b/c)\cdot \overline{1}]$ (Sh–K)
3	$[C_{2}^{1}]$	$[(b\!:\!(c/a))\!:\!2]$	P2	P2	P2	P121
		$[(c\!:\!(a/b))\!:\!2]$				P112
4	$[C_{2}^{2}]$	$[(b\!:\!(c/a))\!:\!2_{1}]$	$[P2_{1}]$	$[P2_{1}]$	$[P2_{1}]$	$[P12_{1}1]$
		$[(c\!:\!(a/b))\!:\!2_{1}]$				$[P112_{1}]$
5	$[C_{2}^{3}]$	$[\left(\displaystyle{a + b \over 2}\bigg/b\!:\!(c/a)\right)\!:\!2]$	C2	C2	C2	C121	B2, B112 (IT, 1952 )
		$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(b/a)\right)\!:\!2]$				A112	$[\left(\displaystyle{a + c \over 2}\bigg/c\!:\!(a/b)\right)\!:\!2]$ (Sh–K)
6	$[C_{2}^{1}]$	$[(b\!:\!(c/a))\cdot m]$	Pm	Pm	Pm	P1m1
		$[(c\!:\!(a/b))\cdot m]$				P11m
7	$[C_{s}^{2}]$	$[(b\!:\!(c/a))\cdot \tilde{c}]$	Pc	Pc	Pc	P1c1	Pb, P11b (IT, 1952 )
		$[(c\!:\!(b/a))\cdot \tilde{a}]$				P11a	$[(c\!:\!(a/b))\cdot \tilde{b}]$ (Sh–K)
8	$[C_{s}^{3}]$	$[\left(\displaystyle{a + b \over 2}\bigg/b\!:\!(c/a)\right)\cdot m]$	Cm	Cm	Cm	C1m1	Bm, B11m (IT, 1952 )
		$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(b/a)\right)\cdot m]$				A11m	$[\left(\displaystyle{a + c \over 2}\bigg/c\!:\!(a/b)\right)\cdot m]$ (Sh–K)
9	$[C_{s}^{4}]$	$[\left(\displaystyle{a + b \over 2}\bigg/b\!:\!(c/a)\right)\cdot \tilde{c}]$	Cc	Cc	Cc	C1c1	Bb, B11b (IT, 1952 )
		$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(b/a)\right)\cdot \tilde{a}]$				A11a	$[\left(\displaystyle{a + c \over 2}\bigg/c\!:\!(a/b)\right)\cdot \tilde{b}]$ (Sh–K)
10	$[C_{2h}^{1}]$	$[(b\!:\!(c/a))\cdot m\!:\!2]$				$[P1\ {2/m}1]$
		$[(c\!:\!(a/b))\cdot m\!:\!2]$				$[P11\ 2/m]$
11	$[C_{2h}^{2}]$	$[(b\!:\!(c/a))\cdot m\!:\!2_{1}]$	$[P2_{1}/m]$	$[P2_{1}/m]$	$[P2_{1}/m]$	$[P1\ 2_{1}/m\ 1]$
		$[(c\!:\!(a/b))\cdot m\!:\!2_{1}]$				$[P11\ 2_{1}/m]$
12	$[C_{2h}^{3}]$	$[\left(\displaystyle{a + b \over 2}\bigg/b\!:\!(c/a)\right)\cdot m\!:\!2]$				$[C1\ 2/m\ 1]$	$[B2/m, B11\ 2/m]$ (IT, 1952 )
		$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(b/a)\right)\cdot m\!:\!2]$				$[A11\ 2/m]$	$[\left(\displaystyle{a + c \over 2}\bigg/c\!:\!(a/b)\right)\cdot m\!:\!2]$ (Sh–K)
13	$[C_{2h}^{4}]$	$[(b\!:\!(c/a))\cdot \tilde{c}\!:\!2]$				$[P1\ 2/c\ 1]$	$[P2/b, P11\ 2/b]$ (IT, 1952 )
		$[(c\!:\!(a/b))\cdot \tilde{a}\!:\!2]$				$[P11\ 2/a]$	$[(c\!:\!(a/b))\cdot \tilde{b}\!:\!2]$ (Sh–K)
14	$[C_{2h}^{5}]$	$[(b\!:\!(c/a))\cdot \tilde{c}\!:\!2_{1}]$	$[P2_{1}/c]$	$[P2_{1}/c]$	$[P2_{1}/c]$	$[P1\ 2_{1}/c\ 1]$	$[P2_{1}/b,P112_{1}/b]$ (IT, 1952 )
		$[(c\!:\!(a/b))\cdot \tilde{a}\!:\!2_{1}]$				$[P11\ 2_{1}/a]$	$[(c\!:\!(a/b))\cdot b\!:\!2_{1}]$ (Sh–K)
15	$[C_{2h}^{6}]$	$[\left(\displaystyle{a + b \over 2}\bigg/b\!:\!(c/a)\right)\cdot \tilde{c}\!:\!2]$				$[C1\ 2/c\ 1]$	$[B2/b, B11\ 2/b]$ (IT, 1952 )
		$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(b/a)\right)\cdot \tilde{a}\!:\!2]$				A11 2a	$[\left(\displaystyle{a + c \over 2}\bigg/c\!:\!(a/b)\right)\cdot \tilde{b}\!:\!2]$ (Sh–K)
16	$[D_{2}^{1}]$	$[(c\!:\!(a\!:\!b))\!:\!2\!:\!2]$	P222	P222	P222	P222
17	$[D_{2}^{2}]$	$[(c\!:\!(a\!:\!b))\!:\!2_{1}\!:\!2]$	$[P222_{1}]$	$[P222_{1}]$	$[P222_{1}]$	$[P222_{1}]$
18	$[D_{2}^{3}]$	$[\def\circcol{\mathop{\bigcirc\hskip -5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!b))\!:\!2\circcol2_{1}]$	$[P2_{1}2_{1}2]$	$[P2_{1}2_{1}2]$	$[P2_{1}2_{1}2]$	$[P2_{1}2_{1}2]$
19	$[D_{2}^{4}]$	$[\def\circcol{\mathop{\bigcirc\hskip -5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!b))\!:\!2_{1}\circcol 2_{1}]$	$[P2_{1}2_{1}2_{1}]$	$[P2_{1}2_{1}2_{1}]$	$[P2_{1}2_{1}2_{1}]$	$[P2_{1}2_{1}2_{1}]$
20	$[D_{2}^{5}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!2_{1}\!:\!2]$	$[C222_{1}]$	$[C222_{1}]$	$[C222_{1}]$	$[C222_{1}]$
21	$[D_{2}^{6}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!2\!:\!2]$	C222	C222	C222	C222
22	$[D_{2}^{7}]$	$[\left(\displaystyle{a + c \over 2}\bigg/{b + c \over 2}\bigg/{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!2\!:\!2]$	F222	F222	F222	F222
23	$[D_{2}^{8}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!2\!:\!2]$	I222	I222	I222	I222
24	$[D_{2}^{9}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!2\!:\!2_{1}]$	$[I2_{1}2_{1}2_{1}]$	$[I2_{1}2_{1}2_{1}]$	$[I2_{1}2_{1}2_{1}]$	$[I2_{1}2_{1}2_{1}]$
25	$[C_{2v}^{1}]$	$[(c\!:\!(a\!:\!b))\!:\!m\cdot 2]$	Pmm	Pmm2	Pmm2	Pmm2
26	$[C_{2v}^{2}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{c}\cdot 2_{1}]$	Pmc	$[Pmc2_{1}]$	$[Pmc2_{1}]$	$[Pmc2_{1}]$
27	$[C_{2v}^{3}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{c}\cdot 2]$	Pcc	Pcc2	Pcc2	Pcc2
28	$[C_{2v}^{4}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{a}\cdot 2]$	Pma	Pma2	Pma2	Pma2
29	$[C_{2v}^{5}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{a}\cdot 2_{1}]$	Pca	$[Pca2_{1}]$	$[Pca2_{1}]$	$[Pca2_{1}]$
30	$[C_{2v}^{6}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{c} \bigodot 2]$	Pnc	Pnc2	Pnc2	Pnc2	$[(c\!:\!(a\!:\!b))\!:\!\widetilde{ac}\cdot 2]$ (Sh–K)
31	$[C_{2v}^{7}]$	$[(c\!:\!(a\!:\!b))\!:\!\widetilde{ac}\cdot 2_{1}]$	Pmn	$[Pmn2_{1}]$	$[Pmn2_{1}]$	$[Pmn2_{1}]$
32	$[C_{2v}^{8}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{a}\bigodot 2]$	Pba	Pba2	Pba2	Pba2
33	$[C_{2v}^{9}]$	$[(c\!:\!(a\!:\!b))\!:\!\tilde{a}\bigodot 2_{1}]$	Pna	$[Pna2_{1}]$	$[Pna2_{1}]$	$[Pna2_{1}]$
34	$[C_{2v}^{10}]$	$[(c\!:\!(a\!:\!b))\!:\!\widetilde{ac}\bigodot 2]$	Pnn	Pnn2	Pnn2	Pnn2
35	$[C_{2v}^{11}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!m\cdot 2]$	Cmm	Cmm2	Cmm2	Cmm2
36	$[C_{2v}^{12}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!\tilde{c}\cdot 2_{1}]$	Cmc	$[Cmc2_{1}]$	$[Cmc2_{1}]$	$[Cmc2_{1}]$
37	$[C_{2v}^{13}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!\tilde{c}\cdot 2]$	Ccc	Ccc2	Ccc2	Ccc2
38	$[C_{2v}^{14}]$	$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!m\cdot 2]$	Amm	Amm2	Amm2	Amm2
39	$[C_{2v}^{15}]$	$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!m\cdot 2_{1}]$	Abm	Abm2	Aem2	Aem2	$[\cases{\!\!\left(\displaystyle{b + c \over 2}\!\big/\!c\!:\!(a\!:\!b)\right)\!:\!\tilde{c}\cdot 2\ (\rm{Sh\!-\!K})\cr \hbox{Use former symbol}\cr Abm2\ \hbox{for generation}\cr}]$
40	$[C_{2v}^{16}]$	$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right.)\!:\!\tilde{a}\cdot 2]$	Ama	Ama2	Ama2	Ama2
41	$[C_{2v}^{17}]$	$[\left(\displaystyle{b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!\tilde{a}\cdot 2_{1}]$	Aba	Aba2	Aea2	Aea2	$[\cases{\!\!\left(\displaystyle{b + c \over 2}\!\big/c\!:\!(a\!:\!b)\right)\!:\!\widetilde{ac}\cdot 2 \ (\rm{Sh\!-\!K})\cr \hbox{Use former symbol}\cr Aba2\ \hbox{for generation}\cr}]$
42	$[C_{2v}^{18}]$	$[\left(\displaystyle{a + c \over 2}\bigg/{b + c \over 2}\bigg/{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\!:\!m\cdot 2]$	Fmm	Fmm2	Fmm2	Fmm2
43	$[C_{2v}^{19}]$	$[\left(\displaystyle{a + c \over 2}\bigg/{b + c \over 2}\bigg/{a + b \over 2}\!:\!\tilde{c}\!:\!(a\!:\!b)\right):\!{1\over 2}\widetilde{ac}\bigodot 2]$	Fdd	Fdd2	Fdd2	Fdd2
44	$[C_{2v}^{20}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!m\cdot 2]$	Imm	Imm2	Imm2	Imm2
45	$[C_{2v}^{21}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!\tilde{c}\cdot 2]$	Iba	Iba2	Iba2	Iba2	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!\tilde{a}\cdot 2_{1}\ \rm(Sh\!-\!K)]$
46	$[C_{2v}^{22}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\!:\!\tilde{a}\cdot 2]$	Ima	Ima2	Ima2	Ima2
47	$[D_{2h}^{1}]$	$[(c\!:\!(a\!:\!b))\cdot m\!:\!2\cdot m]$	Pmmm	$[P2/m\ 2/m\ 2/m]$	Pmmm	$[P2/m\ 2/m\ 2/m]$
48	$[D_{2h}^{2}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \widetilde{ab}\!:\!2\circdot \widetilde{ac}]$	Pnnn	$[P2/n\ 2/n\ 2/n]$	Pnnn	$[P2/n\ 2/n\ 2/n]$
49	$[D_{2h}^{3}]$	$[(c\!:\!(a\!:\!b))\cdot m\!:\!2\cdot \tilde{c}]$	Pccm	$[P2/c\ 2/c\ 2/m]$	Pccm	$[P2/c\ 2/c\ 2/m]$
50	$[D_{2h}^{4}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \widetilde{ab}\!:\!2\circdot \tilde{a}]$	Pban	$[P2/b\ 2/a\ 2/n]$	Pban	$[P2/b\ 2/a\ 2/n]$
51	$[D_{2h}^{5}]$	$[(c\!:\!(a\!:\!b))\cdot \tilde{a}\!:\!2\cdot m]$	Pmma	$[P2_{1}/m\ 2/m\ 2/a]$	Pmma	$[P2_{1}/m\ 2/m\ 2/a]$
52	$[D_{2h}^{6}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \tilde{a}\!:\!2\circdot \widetilde{ac}]$	Pnna	$[P2/n\ 2_{1}/n\ 2/a]$	Pnna	$[P2/n\ 2_{1}/n\ 2/a]$
53	$[D_{2h}^{7}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \tilde{a}\!:\!2_{1}\cdot \widetilde{ac}]$	Pmna	$[P2/m\ 2/n\ 2_{1}/a]$	Pmna	$[P2/m\ 2/n\ 2_{1}/a]$
54	$[D_{2h}^{8}]$	$[(c\!:\!(a\!:\!b))\cdot \tilde{a}\!:\!2\cdot \tilde{c}]$	Pcca	$[P2_{1}/c\ 2/c\ 2/a]$	Pcca	$[P2_{1}/c\ 2/c\ 2/a]$
55	$[D_{2h}^{9}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot m\!:\!2\circdot \tilde{a}]$	Pbam	$[P2_{1}/b\ 2_{1}/a\ 2/m]$	Pbam	$[P2_{1}/b\ 2_{1}/a\ 2/m]$
56	$[D_{2h}^{10}]$	$[(c\!:\!(a\!:\!b))\cdot \widetilde{ab}\!:\!2\cdot \tilde{c}]$	Pccn	$[P2_{1}/c\ 2_{1}/c\ 2/n]$	Pccn	$[P2_{1}/c\ 2_{1}/c\ 2/n]$
57	$[D_{2h}^{11}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot m\!:\!2_{1}\circdot \tilde{c}]$	Pbcm	$[P2/b\ 2_{1}/c\ 2_{1}/m]$	Pbcm	$[P2/b\ 2_{1}/c\ 2_{1}/m]$
58	$[D_{2h}^{12}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot m\!:\!2\circdot \widetilde{ac}]$	Pnnm	$[P2_{1}/n\ 2_{1}/n\ 2/m]$	Pnnm	$[P2_{1}/n\ 2_{1}/n\ 2/m]$
59	$[D_{2h}^{13}]$	$[(c\!:\!(a\!:\!b))\cdot \widetilde{ab}\!:\!2\cdot m]$	Pmmn	$[P2_{1}/m\ 2_{1}/m\ 2/n]$	Pmmn	$[P2_{1}/m\ 2_{1}/m\ 2/n]$
60	$[D_{2h}^{14}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \widetilde{ab}\!:\!2_{1}\circdot \tilde{c}]$	Pbcn	$[P2_{1}/b\ 2/c\ 2_{1}/n]$	Pbcn	$[P2_{1}/b\ 2/c\ 2_{1}/n]$
61	$[D_{2h}^{15}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \tilde{a}\!:\!2_{1}\circdot \tilde{c}]$	Pbca	$[P2_{1}/b\ 2_{1}/c\ 2_{1}/a]$	Pbca	$[P2_{1}/b\ 2_{1}/c\ 2_{1}/a]$
62	$[D_{2h}^{16}]$	$[\def\circdot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!(a\!:\!b))\cdot \tilde{a}\!:\!2_{1}\circdot m]$	Pnma	$[P2_{1}/n\ 2_{1}/m\ 2_{1}/a]$	Pnma	$[P2_{1}/n\ 2_{1}/m\ 2_{1}/a]$
63	$[D_{2h}^{17}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\cdot m\!:\!2_{1}\cdot \tilde{c}]$	Cmcm	$[C2/m\ 2/c\ 2_{1}/m]$	Cmcm	$[C2/m\ 2/c\ 2_{1}/m]$
64	$[D_{2h}^{18}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\cdot \tilde{a}\!:\!2_{1}\cdot \tilde{c}]$	Cmca	$[C2/m\ 2/c\ 2_{1}/a]$	Cmce	$[C2/m\ 2/c\ 2_{1}/e]$	Use former symbol Cmca for generation
65	$[D_{2h}^{19}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\cdot m\!:\!2\cdot m]$	Cmmm	$[C2/m\ 2/m\ 2/m]$	Cmmm	$[C2/m\ 2/m\ 2/m]$
66	$[D_{2h}^{20}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\cdot m\!:\!2\cdot \tilde{c}]$	Cccm	$[C2/c\ 2/c\ 2/m]$	Cccm	$[C2/c\ 2/c\ 2/m]$
67	$[D_{2h}^{21}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\cdot \tilde{a}\!:\!2\cdot m]$	Cmma	$[C2/m\ 2/m\ 2/a]$	Cmme	$[C2/m\ 2/m\ 2/e]$	Use former symbol Cmma for generation
68	$[D_{2h}^{22}]$	$[\left(\displaystyle{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\cdot \tilde{a}\!:\!2\cdot \tilde{c}]$	Ccca	$[C2/c\ 2/c\ 2/a]$	Ccce	$[C2/c\ 2/c\ 2/e]$	Use former symbol Ccca for generation
69	$[D_{2h}^{23}]$	$[\displaylines{\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\hfill\cr \cdot m\!:\!2\cdot m\hfill\cr}]$	Fmmm	$[F2/m\ 2/m\ 2/m]$	Fmmm	$[F2/m\ 2/m\ 2/m]$
70	$[D_{2h}^{24}]$	$[\displaylines{\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!c\!:\!(a\!:\!b)\right)\hfill\cr \cdot {\textstyle{1 \over 2}}\widetilde{ab}\!:\!2\bigodot {\textstyle{1 \over 2}}\widetilde{ac}\hfill\cr}]$	Fddd	$[F2/d\ 2/d\ 2/d]$	Fddd	$[F2/d\ 2/d\ 2/d]$
71	$[D_{2h}^{25}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\cdot m\!:\!2\cdot m]$	Immm	$[I2/m\ 2/m\ 2/m]$	Immm	I2/m 2/m 2/m
72	$[D_{2h}^{26}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\cdot m\!:\!2\cdot \tilde{c}]$	Ibam	$[I2/b\ 2/a\ 2/m]$	Ibam	$[I2/b\ 2/a\ 2/m]$
73	$[D_{2h}^{27}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\cdot \tilde{a}\!:\!2\cdot \tilde{c}]$	Ibca	$[I2_{1}/b\ 2_{1}/c\ 2_{1}/a]$	Ibca	$[I2_{1}/b\ 2_{1}/c\ 2_{1}/a]$	$[I2/b\ 2/c\ 2/a]$ (IT, 1952 )
74	$[D_{2h}^{28}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!b)\right)\cdot \tilde{a}\!:\!2\cdot m]$	Imma	$[I2_{1}/m\ 2_{1}/m\ 2_{1}/a]$	Imma	$[I2_{1}/m\ 2_{1}/m\ 2_{1}/a]$	$[I2/m\ 2/m\ 2/a]$ (IT, 1952 )
75	$[C_{4}^{1}]$	$[(c\!:\!(a\!:\!a))\!:\!4]$	P4	P4	P4	P4
76	$[C_{4}^{2}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{1}]$	$[P4_{1}]$	$[P4_{1}]$	$[P4_{1}]$	$[P4_{1}]$
77	$[C_{4}^{3}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{2}]$	$[P4_{2}]$	$[P4_{2}]$	$[P4_{2}]$	$[P4_{2}]$
78	$[C_{4}^{4}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{3}]$	$[P4_{3}]$	$[P4_{3}]$	$[P4_{3}]$	$[P4_{3}]$
79	$[C_{4}^{5}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4]$	I4	I4	I4	I4
80	$[C_{4}^{6}]$	$[\left(\displaystyle{a - b - c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4_{1}]$	$[I4_{1}]$	$[I4_{1}]$	$[I4_{1}]$	$[I4_{1}]$
81	$[S_{4}^{1}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}]$	$[P\overline{4}]$	$[P\overline{4}]$	$[P\overline{4}]$	$[P\overline{4}]$
82	$[S_{4}^{2}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!\tilde{4}]$	$[I\overline{4}]$	$[I\overline{4}]$	$[I\overline{4}]$	$[I\overline{4}]$
83	$[C_{4h}^{1}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4]$
84	$[C_{4h}^{2}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4_{2}]$	$[P4_{2}/m]$	$[P4_{2}/m]$	$[P4_{2}/m]$	$[P4_{2}/m]$
85	$[C_{4h}^{3}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4]$
86	$[C_{4h}^{4}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4_{2}]$	$[P4_{2}/n]$	$[P4_{2}/n]$	$[P4_{2}/n]$	$[P4_{2}/n]$
87	$[C_{4h}^{5}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\cdot m\!:\!4]$
88	$[C_{4h}^{6}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\cdot \tilde{a}\!:\!4_{1}]$	$[I4_{1}/a]$	$[I4_{1}/a]$	$[I4_{1}/a]$	$[I4_{1}/a]$
89	$[D_{4}^{1}]$	(c:(a:a)):4:2	P42	P422	P422	P422
90	$[D_{4}^{2}]$	$[\def\circcol{\mathop{\bigcirc\hskip -5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!a))\!:\!4 \circcol 2_{1}]$	$[P42_{1}]$	$[P42_{1}2]$	$[P42_{1}2]$	$[P42_{1}2]$
91	$[D_{4}^{3}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{1}\!:\!2]$	$[P4_{1}2]$	$[P4_{1}22]$	$[P4_{1}22]$	$[P4_{1}22]$
92	$[D_{4}^{4}]$	$[\def\circcol{\mathop{\bigcirc\hskip -5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!a))\!:\!4_{1}\circcol 2_{1}]$	$[P4_{1}2_{1}]$	$[P4_{1}2_{1}2]$	$[P4_{1}2_{1}2]$	$[P4_{1}2_{1}2]$
93	$[D_{4}^{5}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{2}\!:\!2]$	$[P4_{2}2]$	$[P4_{2}22]$	$[P4_{2}22]$	$[P4_{2}22]$
94	$[D_{4}^{6}]$	$[\def\circcol{\mathop{\bigcirc\hskip -5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!a))\!:\!4_{2}\circcol 2_{1}]$	$[P4_{2}2_{1}]$	$[P4_{2}2_{1}2]$	$[P4_{2}2_{1}2]$	$[P4_{2}2_{1}2]$
95	$[D_{4}^{7}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{3}\!:\!2]$	$[P4_{3}2]$	$[P4_{3}22]$	$[P4_{3}22]$	$[P4_{3}22]$
96	$[D_{4}^{8}]$	$[\def\circcol{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!a))\!:\!4_{3}\circcol 2_{1}]$	$[P4_{3}2_{1}]$	$[P4_{3}2_{1}2]$	$[P4_{3}2_{1}2]$	$[P4_{3}2_{1}2]$
97	$[D_{4}^{9}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4\!:\!2]$	I42	I422	I422	I422
98	$[D_{4}^{10}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4_{1}\!:\!2]$	$[I4_{1}2]$	$[I4_{1}22]$	$[I4_{1}22]$	$[I4_{1}22]$
99	$[C_{4v}^{1}]$	$[(c\!:\!(a\!:\!a))\!:\!4\cdot m]$	P4mm	P4mm	P4mm	P4mm
100	$[C_{4v}^{2}]$	$[ (c\!:\!(a\!:\!a))\!:\!4\bigodot \tilde{a}]$	P4bm	P4bm	P4bm	P4bm
101	$[C_{4v}^{3}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{2}\cdot \tilde{c}]$	P4cm	$[P4_{2}cm]$	$[P4_{2}cm]$	$[P4_{2}cm]$
102	$[C_{4v}^{4}]$	$[ (c\!:\!(a\!:\!a))\!:\!4_{2}\bigodot \widetilde{ac}]$	P4nm	$[P4_{2}nm]$	$[P4_{2}nm]$	$[P4_{2}nm]$
103	$[C_{4v}^{5}]$	$[(c\!:\!(a\!:\!a))\!:\!4\cdot \tilde{c}]$	P4cc	P4cc	P4cc	P4cc
104	$[C_{4v}^{6}]$	$[ (c\!:\!(a\!:\!a))\!:\!4\bigodot \widetilde{ac}]$	P4nc	P4nc	P4nc	P4nc
105	$[C_{4v}^{7}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{2}\cdot m]$	P4mc	$[P4_{2}mc]$	$[P4_{2}mc]$	$[P4_{2}mc]$
106	$[C_{4v}^{8}]$	$[(c\!:\!(a\!:\!a))\!:\!4_{2}\bigodot \tilde{a}]$	P4bc	$[P4_{2}bc]$	$[P4_{2}bc]$	$[P4_{2}bc]$
107	$[C_{4v}^{9}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4\cdot m]$	I4mm	I4mm	I4mm	I4mm
108	$[C_{4v}^{10}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4\cdot \tilde{c}]$	I4cm	I4cm	I4cm	I4cm
109	$[C_{4v}^{11}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4_{1}\bigodot m]$	I4md	$[I4_{1}md]$	$[I4_{1}md]$	$[I4_{1}md]$
110	$[C_{4v}^{12}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!4_{1}\bigodot \tilde{c}]$	I4cd	$[I4_{1}cd]$	$[I4_{1}cd]$	$[I4_{1}cd]$	$[\left(\displaystyle{a + b + c \over 2}\!\!\bigg/\!\!c\!:\!a\!:\!a\right)\!:\!4_{1}\cdot \tilde{a}\ (\rm{Sh\!-\!K})]$
111	$[D_{2d}^{1}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\!:\!2]$	$[P\overline{4}2m]$	$[P\overline{4}2m]$	$[P\overline{4}2m]$	$[P\overline{4}2m]$
112	$[D_{2d}^{2}]$	$[\def\circcol{\mathop{\bigcirc\hskip -5pt{\raise.05pt\hbox{$\!:\!$}} \ }} (c\!:\!(a\!:\!a))\!:\!\tilde{4}\circcol 2]$	$[P\overline{4}2c]$	$[P\overline{4}2c]$	$[P\overline{4}2c]$	$[P\overline{4}2c]$
113	$[D_{2d}^{3}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\cdot \widetilde{ab}]$	$[P\overline{4}2_{1}m]$	$[P\overline{4}2_{1}m]$	$[P\overline{4}2_{1}m]$	$[P\overline{4}2_{1}m]$
114	$[D_{2d}^{4}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\cdot \widetilde{abc}]$	$[P\overline{4}2_{1}c]$	$[P\overline{4}2_{1}c]$	$[P\overline{4}2_{1}c]$	$[P\overline{4}2_{1}c]$
115	$[D_{2d}^{5}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\cdot m]$	$[C\overline{4}2m]$	$[C\overline{4}2m]$	$[P\overline{4}m2]$	$[P\overline{4}m2]$
116	$[D_{2d}^{6}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\cdot \tilde{c}]$	$[C\overline{4}2c]$	$[C\overline{4}2c]$	$[P\overline{4}c2]$	$[P\overline{4}c2]$
117	$[D_{2d}^{7}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\bigodot \tilde{a}]$	$[C\overline{4}2b]$	$[C\overline{4}2b]$	$[P\overline{4}b2]$	$[P\overline{4}b2]$
118	$[D_{2d}^{8}]$	$[(c\!:\!(a\!:\!a))\!:\!\tilde{4}\cdot \widetilde{ac}]$	$[C\overline{4}2n]$	$[C\overline{4}2n]$	$[P\overline{4}n2]$	$[P\overline{4}n2]$
119	$[D_{2d}^{9}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!\tilde{4}\cdot m]$	$[F\overline{4}2m]$	$[F\overline{4}2m]$	$[I\overline{4}m2]$	$[I\overline{4}m2]$
120	$[D_{2d}^{10}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!\tilde{4}\cdot \tilde{c}]$	$[F\overline{4}2c]$	$[F\overline{4}2c]$	$[I\overline{4}c2]$	$[I\overline{4}c2]$
121	$[D_{2d}^{11}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!\tilde{4}\!:\!2]$	$[I\overline{4}2m]$	$[I\overline{4}2m]$	$[I\overline{4}2m]$	$[I\overline{4}2m]$
122	$[D_{2d}^{12}]$	$[\left(\displaystyle{a + b + c \over 2}\bigg/c\!:\!(a\!:\!a)\right)\!:\!\tilde{4}\bigodot {1 \over 2}\widetilde{abc}]$	$[I\overline{4}2d]$	$[I\overline{4}2d]$	$[I\overline{4}2d]$	$[I\overline{4}2d]$
123	$[D_{4h}^{1}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4\cdot m]$		$[P4/m\ 2/m\ 2/m]$		$[P4/m\ 2/m\ 2/m]$
124	$[D_{4h}^{2}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4\cdot \tilde{c}]$		$[P4/m\ 2/c\ 2/c]$		$[P4/m\ 2/c\ 2/c]$
125	$[D_{4h}^{3}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4\bigodot \tilde{a}]$		$[P4/n\ 2/b\ 2/m]$		$[P4/n\ 2/b\ 2/m]$	$[\def\bigodot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!a\!:\!a)\cdot \widetilde{ab}\!:\!4\bigodot \tilde{b}]$ (Sh–K)
126	$[D_{4h}^{4}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4\bigodot \widetilde{ac}]$		$[P4/n\ 2/n\ 2/c]$		$[P4/n\ 2/n\ 2/c]$
127	$[D_{4h}^{5}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4\bigodot \tilde{a}]$		$[P4/m\ 2_{1}/b\ 2/m]$		$[P4/m\ 2_{1}/b\ 2/m]$	$[\def\bigodot{\mathop{\bigcirc\hskip -6.5pt{\raise.05pt\hbox{$\cdot$}} \ }} (c\!:\!a\!:\!a)\cdot m\!:\!4\bigodot \tilde{b}]$ (Sh–K)
128	$[D_{4h}^{6}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4\bigodot \widetilde{ac}]$		$[P4/m\ 2_{1}/n\ 2/c]$		$[P4/m\ 2_{1}/n\ 2/c]$
129	$[D_{4h}^{7}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4\cdot m]$		$[P4/n\ 2_{1}/m\ 2/m]$		$[P4/n\ 2_{1}/m\ 2/m]$
130	$[D_{4h}^{8}]$	$[(c\!:\!(a\!:\!a)\cdot \widetilde{ab}\!:\!4\cdot \tilde{c}]$		$[P4/n\ 2/c\ 2/c]$		$[P4/n\ 2/c\ 2/c]$
131	$[D_{4h}^{9}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4_{2}\cdot m]$		$[P4_{2}/m\ 2/m\ 2/c]$	$[P4_{2}/mmc]$	$[P4_{2}/m\ 2/m\ 2/c]$
132	$[D_{4h}^{10}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4_{2}\cdot \tilde{c}]$		$[P4_{2}/m\ 2/c\ 2/m]$	$[P4_{2}/mcm]$	$[P4_{2}/m\ 2/c\ 2/m]$
133	$[D_{4h}^{11}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4_{2}\bigodot \tilde{a}]$		$[P4_{2}/n\ 2/b\ 2/c]$	$[P4_{2}/nbc]$	$[P4_{2}/n\ 2/b\ 2/c]$	$[(c\!:\!a\!:\!a)\cdot \widetilde{ab}\!:\!4_{2}\bigodot \tilde{b}]$ (Sh–K)
134	$[D_{4h}^{12}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4_{2}\bigodot \widetilde{ac}]$		$[P4_{2}/n\ 2/n\ 2/m]$	$[P4_{2}/nnm]$	$[P4_{2}/n\ 2/n\ 2/m]$
135	$[D_{4h}^{13}]$	$[(c\!:\!(a\!:\!a))\cdot n\!:\!4_{2}\bigodot \tilde{a}]$		$[P4_{2}/m\ 2_{1}/b\ 2/c]$	$[P4_{2}/mbc]$	$[P4_{2}/m\ 2_{1}/b\ 2/c]$	$[(c\!:\!a\!:\!a)\cdot m\!:\!4_{2}\bigodot \tilde{b}]$ (Sh–K)
136	$[D_{4h}^{14}]$	$[(c\!:\!(a\!:\!a))\cdot m\!:\!4_{2}\bigodot \widetilde{ac}]$		$[P4_{2}/m\ 2_{1}/n\ 2/m]$	$[P4_{2}/mnm]$	$[P4_{2}/m\ 2_{1}/n\ 2/m]$
137	$[D_{4h}^{15}]$	$[(c\!:\!(a\!:\!a))\cdot \widetilde{ab}\!:\!4_{2}\cdot m]$		$[P4_{2}/n\ 2_{1}/m\ 2/c]$	$[P4_{2}/nmc]$	$[P4_{2}/n\ 2_{1}/m\ 2/c]$
138	$[D_{4h}^{16}]$	$[(c\!:\!(a\!:\!a))\cdot ab\!:\!4_{2}\cdot \tilde{c}]$		$[P4_{2}/n\ 2_{1}/c\ 2/m]$	$[P4_{2}/ncm]$	$[P4_{2}/n\ 2_{1}/c\ 2/m]$
139	$[D_{4h}^{17}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!c\!:\!(a\!:\!a)\right)\cdot m\!:\!4\cdot m]$		$[I4/m\ 2/m\ 2/m]$		$[I4/m\ 2/m\ 2/m]$
140	$[D_{4h}^{18}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!c\!:\!(a\!:\!a)\right)\cdot m\!:\!4\cdot \tilde{c}]$		$[I4/m\ 2/c\ 2/m]$		$[I4/m\ 2/c\ 2/m]$
141	$[D_{4h}^{19}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!c\!:\!(a\!:\!a)\right)\cdot \tilde{a}\!:\!4_{1}\bigodot m]$		$[I4_{1}/a\ 2/m\ 2/d]$	$[I4_{1}/amd]$	$[I4_{1}/a\ 2/m\ 2/d]$
142	$[D_{4h}^{20}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!c\!:\!(a\!:\!a)\right)\cdot \tilde{a}\!:\!4_{1}\bigodot \tilde{c}]$		$[I4_{1}/a\ 2/c\ 2/d]$	$[I4_{1}/acd]$	$[I4_{1}/a\ 2/c\ 2/d]$
143	$[C_{3}^{1}]$	$[(c\!:\!(a/a))\!:\!3]$	C3	C3	P3	P3
144	$[C_{3}^{2}]$	$[(c\!:\!(a/a))\!:\!3_{1}]$	$[C3_{1}]$	$[C3_{1}]$	$[P3_{1}]$	$[P3_{1}]$
145	$[C_{3}^{3}]$	$[(c\!:\!(a/a))\!:\!3_{2}]$	$[C3_{2}]$	$[C3_{2}]$	$[P3_{2}]$	$[P3_{2}]$
146	$[C_{3}^{4}]$	$[\left(\displaystyle{2a + b + c \over 3}\!\!\bigg/\!\!{a + 2b + 2c \over 3}\!\!\bigg/\!\!c\!:\!(a/a)\right)\!:\!3]$	R3	R3	R3	R3	Hexagonal setting (Sh–K)
							Rhombohedral setting (Sh–K)
147	$[C_{3i}^{1}]$	$[(c\!:\!(a/a))\!:\!\tilde{6}]$	$[C\overline{3}]$	$[C\overline{3}]$	$[P\overline{3}]$	$[P\overline{3}]$
148	$[C_{3i}^{2}]$	$[\left(\displaystyle{2a + b + c \over 3}\!\bigg/\!{a + 2b + 2c \over 3}\!\bigg/\!c\!:\!(a/a)\right)\!:\!\tilde{6}]$	$[R\overline{3}]$	$[R\overline{3}]$	$[R\overline{3}]$	$[R\overline{3}]$	Hexagonal setting (Sh–K)
		$[(a/a/a)/\tilde{6}]$					Rhombohedral setting (Sh–K)
149	$[D_{3}^{1}]$	$[(c\!:\!(a/a))\!:\!2\!:\!3]$	H32	H321	P312	P312
150	$[D_{3}^{2}]$	$[(c\!:\!(a/a))\!:\!2\!:\!3]$	C32	C321	P321	P321
151	$[D_{3}^{3}]$	$[(c\!:\!(a/a))\!:\!2\!:\!3_{1}]$	$[H3_{1}2]$	$[H3_{1}21]$	$[P3_{1}12]$	$[P3_{1}12]$
152	$[D_{3}^{4}]$	$[(c\!:\!(a/a))\!:\!2\!:\!3_{1}]$	$[C3_{1}2]$	$[C3_{1}21]$	$[P3_{1}21]$	$[P3_{1}21]$
153	$[D_{3}^{5}]$	$[(c\!:\!(a/a))\!:\!2\!:\!3_{2}]$	$[H3_{2}2]$	$[H3_{2}21]$	$[P3_{2}12]$	$[P3_{2}12]$
154	$[D_{3}^{6}]$	$[(c\!:\!(a/a))\!:\!2\!:\!3_{2}]$	$[C3_{2}2]$	$[C3_{2}21]$	$[P3_{2}21]$	$[P3_{2}21]$
155	$[D_{3}^{7}]$	$[\displaylines{\left(\displaystyle{2a + b + c \over 3}\!\bigg/\!{a + 2b + 2c \over 3}\!\bigg/\!c\!:\!(a/a)\right)\hfill\cr \cdot 2\!:\!3\hfill\cr}]$	R32	R32	R32	R32	Hexagonal setting (Sh–K)
		$[(a/a/a)/3\!:\!2]$					Rhombohedral setting (Sh–K)
156	$[C_{3v}^{1}]$	$[(c\!:\!(a/a))\!:\!m\!:\!3]$	C3m	C3ml	P3ml	P3ml
157	$[C_{3v}^{2}]$	$[(a\!:\!c\!:\!a)\!:\!m\!:\!3]$	H3m	H3ml	P3lm	P3lm	$[\!\matrix{(c\!:\!(a/a))\cdot m\cdot 3 \rm{(Sh\!-\!K)}\hfill\cr\quad\hbox{with special comment}\hfill\cr}]$
158	$[C_{3v}^{3}]$	$[(c\!:\!(a/a))\!:\!\tilde{c}\!:\!3]$	C3c	C3cl	P3cl	P3cl
159	$[C_{3v}^{4}]$	$[(a\!:\!c\!:\!a)\!:\!\tilde{c}\!:\!3]$	H3c	H3cl	P3lc	P3lc	$[\!\matrix{(c\!:\!(a/a))\cdot \tilde{c}\cdot 3 \rm{(Sh\!-\!K)}\hfill\cr \quad\hbox{with special comment}\hfill\cr}]$
160	$[C_{3v}^{5}]$	$[\left(\displaystyle{2a + b + c \over 3}\!\bigg/\!{a + 2b + 2c \over 3}\!\bigg/\!c\!:\!(a/a)\right) \cdot m\cdot 3]$	R3m	R3m	R3m	R3m	Hexagonal setting (Sh–K)
		$[(a/a/a)/3\cdot m]$					Rhombohedral setting (Sh–K)
161	$[C_{3v}^{6}]$	$[\left(\displaystyle{2a + b + c \over 3}\!\bigg/\!{a + 2b + 2c \over 3}\!\bigg/\!c\!:\!(a/a)\right) \cdot \tilde{c}\cdot 3]$	R3c	R3c	R3c	R3c	Hexagonal setting (Sh–K)
		$[(a/a/a)/3\cdot \widetilde{abc}]$					Rhombohedral setting (Sh–K)
162	$[D_{3d}^{1}]$	$[(a\!:\!c\!:\!a)\cdot m\cdot \tilde{6}]$	$[H\overline{3}m]$	$[H\overline{3}\ 2/m\ 1]$	$[P\overline{3}1m]$	$[P\overline{3}1\ 2/m]$	$[(c\!:\!(a/a))\cdot m\cdot \tilde{6}]$ (Sh–K) with special comment
163	$[D_{3d}^{2}]$	$[(a\!:\!c\!:\!a)\cdot \tilde{c}\cdot \tilde{6}]$	$[H\overline{3}c]$	$[H\overline{3}\ 2/c\ 1]$	$[P\overline{3}1c]$	$[P\overline{3}1\ 2/c]$	$[(c\!:\!(a/a)\cdot \tilde{c}\cdot \tilde{6}]$ (Sh–K) with special comment
164	$[D_{3d}^{3}]$	$[(c\!:\!(a/a))\!:\!m\cdot \tilde{6}]$	$[C\overline{3}m]$	$[C\overline{3}\ 2/m\ 1]$	$[P\overline{3}m1]$	$[P\overline{3}\ 2/m\ 1]$
165	$[D_{3d}^{4}]$	$[(c\!:\!(a/a))\!:\!\tilde{c}\cdot \tilde{6}]$	$[C\overline{3}c]$	$[C\overline{3}\ 2/c\ 1]$	$[P\overline{3}c1]$	$[P\overline{3}\ 2/c\ 1]$
166	$[D_{3d}^{5}]$	$[\left(\displaystyle{2a + b + c \over 3}\!\bigg/\!{a + 2b + 2c \over 3}\!\bigg/\!c\!:\!(a/a)\right) :\!m\cdot \tilde{6}]$	$[R\overline{3}m]$	$[R\overline{3}\ 2/m]$	$[R\overline{3}m]$	$[R\overline{3}\ 2/m]$	Hexagonal setting (Sh–K)
		$[(a/a/a)/\tilde{6}\cdot m]$					Rhombohedral setting (Sh–K)
167	$[D_{3d}^{6}]$	$[\left(\displaystyle{2a + b + c \over 3}\!\bigg/\!{a + 2b + 2c \over 3}\!\bigg/\!c\!:\!(a/a)\right):\!\tilde{c}\cdot \tilde{6}]$	$[R\overline{3}c]$	$[R\overline{3}\ 2/c]$	$[R\overline{3}c]$	$[R\overline{3}\ 2/c]$	Hexagonal setting (Sh–K)
		$[(a/a/a)/\tilde{6}\cdot \widetilde{abc}]$					Rhombohedral setting (Sh–K)
168	$[C_{6}^{1}]$	$[(c\!:\!(a/a))\!:\!6]$	C6	C6	P6	P6
169	$[C_{6}^{2}]$	$[(c\!:\!(a/a))\!:\!6_{1}]$	$[C6_{1}]$	$[C6_{1}]$	$[P6_{1}]$	$[P6_{1}]$
170	$[C_{6}^{3}]$	$[(c\!:\!(a/a))\!:\!6_{5}]$	$[C6_{5}]$	$[C6_{5}]$	$[P6_{5}]$	$[P6_{5}]$
171	$[C_{6}^{4}]$	$[(c\!:\!(a/a))\!:\!6_{2}]$	$[C6_{2}]$	$[C6_{2}]$	$[P6_{2}]$	$[P6_{2}]$
172	$[C_{6}^{5}]$	$[(c\!:\!(a/a))\!:\!6_{4}]$	$[C6_{4}]$	$[C6_{4}]$	$[P6_{4}]$	$[P6_{4}]$
173	$[C_{6}^{6}]$	$[(c\!:\!(a/a))\!:\!6_{3}]$	$[C6_{3}]$	$[C6_{3}]$	$[P6_{3}]$	$[P6_{3}]$
174	$[C_{3h}^{1}]$	$[(c\!:\!(a/a))\!:\!3\!:\!m]$	$[C\overline{6}]$	$[C\overline{6}]$	$[P\overline{6}]$	$[P\overline{6}]$
175	$[C_{6h}^{1}]$	$[(c\!:\!(a/a))\cdot m\!:\!6]$
176	$[C_{6h}^{2}]$	$[(c\!:\!(a/a))\cdot m\!:\!6_{3}]$	$[C6_{3}/m]$	$[C6_{3}/m]$	$[P6_{3}/m]$	$[P6_{3}/m]$
177	$[D_{6}^{1}]$	$[(c\!:\!(a/a))\cdot 2\!:\!6]$	C62	C622	P622	P622
178	$[D_{6}^{2}]$	$[(c\!:\!(a/a))\cdot 2\!:\!6_{1}]$	$[C6_{1}2]$	$[C6_{1}22]$	$[P6_{1}22]$	$[P6_{1}22]$
179	$[D_{6}^{3}]$	$[(c\!:\!(a/a))\cdot 2\!:\!6_{5}]$	$[C6_{5}2]$	$[C6_{5}22]$	$[P6_{5}22]$	$[P6_{5}22]$
180	$[D_{6}^{4}]$	$[(c\!:\!(a/a))\cdot 2\!:\!6_{2}]$	$[C6_{2}2]$	$[C6_{2}22]$	$[P6_{2}22]$	$[P6_{2}22]$
181	$[D_{6}^{5}]$	$[(c\!:\!(a/a))\cdot 2\!:\!6_{4}]$	$[C6_{4}2]$	$[C6_{4}22]$	$[P6_{4}22]$	$[P6_{4}22]$
182	$[D_{6}^{6}]$	$[(c\!:\!(a/a))\cdot 2\!:\!6_{3}]$	$[C6_{3}2]$	$[C6_{3}22]$	$[P6_{3}22]$	$[P6_{3}22]$
183	$[C_{6v}^{1}]$	$[(c\!:\!(a/a))\!:\!m\cdot 6]$	C6mm	C6mm	P6mm	P6mm
184	$[C_{6v}^{2}]$	$[(c\!:\!(a/a))\!:\!\tilde{c}\cdot 6]$	C6cc	C6cc	P6cc	P6cc
185	$[C_{6v}^{3}]$	$[(c\!:\!(a/a))\!:\!\tilde{c}\cdot 6_{3}]$	C6cm	$[C6_{3}cm]$	$[P6_{3}cm]$	$[P6_{3}cm]$
186	$[C_{6v}^{4}]$	$[(c\!:\!(a/a))\!:\!m\cdot 6_{3}]$	C6mc	$[C6_{3}mc]$	$[P6_{3}mc]$	$[P6_{3}mc]$
187	$[D_{3h}^{1}]$	$[(c\!:\!(a/a))\!:\!m\cdot 3\!:\!m]$	$[C\overline{6}m2]$	$[C\overline{6}m2]$	$[P\overline{6}m2]$	$[P\overline{6}m2]$
188	$[D_{3h}^{2}]$	$[(c\!:\!(a/a))\!:\!\tilde{c}\cdot 3\!:\!m]$	$[C\overline{6}c2]$	$[C\overline{6}c2]$	$[P\overline{6}c2]$	$[P\overline{6}c2]$
189	$[D_{3h}^{3}]$	$[(c\!:\!(a/a))\cdot m\!:\!3\cdot m]$	$[H\overline{6}m2]$	$[H\overline{6}m2]$	$[P\overline{6}2m]$	$[P\overline{6}2m]$
190	$[D_{3h}^{4}]$	$[(c\!:\!(a/a))\cdot m\!:\!3\cdot \tilde{c}]$	$[H\overline{6}c2]$	$[H\overline{6}c2]$	$[P\overline{6}2c]$	$[P\overline{6}2c]$
191	$[D_{6h}^{1}]$	$[(c\!:\!(a/a))\cdot m\!:\!6\cdot m]$		$[C6/m\ 2/m\ 2/m]$		$[P6/m\ 2/m\ 2/m]$
192	$[D_{6h}^{2}]$	$[(c\!:\!(a/a))\cdot m\!:\!6\cdot \tilde{c}]$		$[C6/m\ 2/c\ 2/c]$		$[P6/m\ 2/c\ 2/c]$
193	$[D_{6h}^{3}]$	$[(c\!:\!(a/a))\cdot m\!:\!6_{3}\cdot \tilde{c}]$		$[C6_{3}/m\ 2/c\ 2/m]$	$[P6_{3}/mcm]$	$[P6_{3}/m\ 2/c\ 2/m]$
194	$[D_{6h}^{4}]$	$[(c\!:\!(a/a))\cdot m\!:\!6_{3}\cdot m]$		$[C6_{3}/m\ 2/m\ 2/c]$	$[P6_{3}/mmc]$	$[P6_{3}/m\ 2/m\ 2/c]$
195	$[T^{1}]$	$[(a\!:\!(a/a))\!:\!2/3]$	P23	P23	P23	P23
196	$[T^{2}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right)\!:\!2/3]$	F23	F23	F23	F23
197	$[T^{3}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!2/3]$	I23	I23	I23	I23
198	$[T^{4}]$	$[(a\!:\!(a\!:\!a))\!:\!2_{1}//3]$	$[P2_{1}3]$	$[P2_{1}3]$	$[P2_{1}3]$	$[P2_{1}3]$
199	$[T^{5}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!2_{1}//3]$	$[I2_{1}3]$	$[I2_{1}3]$	$[I2_{1}3]$	$[I2_{1}3]$
200	$[T_{h}^{1}]$	$[(a\!:\!(a\!:\!a))\cdot m/\tilde{6}]$	Pm3	$[P2/m\ \overline{3}]$	$[Pm\overline{3}]$	$[P2/m\ \overline{3}]$	Pm3 (IT, 1952 )
201	$[T_{h}^{2}]$	$[(a\!:\!(a\!:\!a))\cdot \widetilde{ab}/\tilde{6}]$	Pn3	$[P2/n\ \overline{3}]$	$[Pn\overline{3}]$	$[P2/n\ \overline{3}]$	Pn3 (IT, 1952 )
202	$[T_{h}^{3}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right)\cdot m/\tilde{6}]$	Fm3	$[F2/m\ \overline{3}]$	$[Fm\overline{3}]$	$[F2/m\ \overline{3}]$	Fm3 (IT, 1952 )
203	$[T_{h}^{4}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right) \cdot {1 \over 2}ab/\tilde{6}]$	Fd3	$[F2/d\ \overline{3}]$	$[Fd\overline{3}]$	$[F2/d\ \overline{3}]$	Fd3 (IT, 1952 )
204	$[T_{h}^{5}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\cdot m/\tilde{6}]$	Im3	$[I2/m\ \overline{3}]$	$[Im\overline{3}]$	$[I2/m\ \overline{3}]$	Im3 (IT, 1952 )
205	$[T_{h}^{6}]$	$[(a\!:\!(a\!:\!a))\cdot \tilde{a}/\tilde{6}]$	Pa3	$[P2_{1}/a\ \overline{3}]$	$[Pa\overline{3}]$	$[P2_{1}/a\ \overline{3}]$	Pa3 (IT, 1952 )
206	$[T_{h}^{7}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\cdot \tilde{a}/\tilde{6}]$	Ia3	$[I2_{1}/a\ \overline{3}]$	$[Ia\overline{3}]$	$[I2_{1}/a\ \overline{3}]$	Ia3 (IT, 1952 )
207	$[O^{1}]$	$[(a\!:\!(a\!:\!a))\!:\!4/3]$	P43	P432	P432	P432
208	$[O^{2}]$	$[(a\!:\!(a\!:\!a))\!:\!4_{2}//3]$	$[P4_{2}3]$	$[P4_{2}32]$	$[P4_{2}32]$	$[P4_{2}32]$
209	$[O^{3}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right)\!:\!4/3]$	F43	F432	F432	F432
210	$[O^{4}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right) \!:\!4_{1}//3]$	$[F4_{1}3]$	$[F4_{1}32]$	$[F4_{1}32]$	$[F4_{1}32]$
211	$[O^{5}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!4/3]$	I43	I432	I432	I432
212	$[O^{6}]$	$[(a\!:\!(a\!:\!a))\!:\!4_{3}//3]$	$[P4_{3}3]$	$[P4_{3}32]$	$[P4_{3}32]$	$[P4_{3}32]$
213	$[O^{7}]$	$[(a\!:\!(a\!:\!a))\!:\!4_{1}//3]$	$[P4_{1}3]$	$[P4_{1}32]$	$[P4_{1}32]$	$[P4_{1}32]$
214	$[O^{8}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!4_{1}//3]$	$[I4_{1}3]$	$[I4_{1}32]$	$[I4_{1}32]$	$[I4_{1}32]$
215	$[T_{d}^{1}]$	$[(a\!:\!(a\!:\!a))\!:\!\tilde{4}/3]$	$[P\overline{4}3m]$	$[P\overline{4}3m]$	$[P\overline{4}3m]$	$[P\overline{4}3m]$
216	$[T_{d}^{2}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right)\!:\!\tilde{4}/3]$	$[F\overline{4}3m]$	$[F\overline{4}3m]$	$[F\overline{4}3m]$	$[F\overline{4}3m]$
217	$[T_{d}^{3}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right) \!:\!\tilde{4}/3]$	$[I\overline{4}3m]$	$[I\overline{4}3m]$	$[I\overline{4}3m]$	$[I\overline{4}3m]$
218	$[T_{d}^{4}]$	$[(a\!:\!(a\!:\!a))\!:\!\tilde{4}//3]$	$[P\overline{4}3n]$	$[P\overline{4}3n]$	$[P\overline{4}3n]$	$[P\overline{4}3n]$
219	$[T_{d}^{5}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right)\!:\!\tilde{4}//3]$	$[F\overline{4}3c]$	$[F\overline{4}3c]$	$[F\overline{4}3c]$	$[F\overline{4}3c]$
220	$[T_{d}^{6}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!\tilde{4}//3]$	$[I\overline{4}3d]$	$[I\overline{4}3d]$	$[I\overline{4}3d]$	$[I\overline{4}3d]$
221	$[O_{h}^{1}]$	$[(a\!:\!(a\!:\!a))\!:\!4/\tilde{6}\cdot m]$	Pm3m	$[P4/m\ \overline{3}\ 2/m]$	$[Pm\overline{3}m]$	$[P4/m\ \overline{3}\ 2/m]$	Pm3m (IT, 1952 )
222	$[O_{h}^{2}]$	$[(a\!:\!(a\!:\!a))\!:\!4/\tilde{6}\cdot \widetilde{abc}]$	Pn3n	$[P4/n\ \overline{3}\ 2/n]$	$[Pn\overline{3}n]$	$[P4/n\ \overline{3}\ 2/n]$	Pn3n (IT, 1952 )
223	$[O_{h}^{3}]$	$[(a\!:\!(a\!:\!a))\!:\!4_{2}//\tilde{6}\cdot \widetilde{abc}]$	Pm3n	$[P4_{2}/m\ \overline{3}\ 2/n]$	$[Pm\overline{3}n]$	$[P4_{2}/m\ \overline{3}\ 2/n]$	Pm3n (IT, 1952 )
224	$[O_{h}^{4}]$	$[(a\!:\!(a\!:\!a))\!:\!4_{2}//\tilde{6}\cdot m]$	Pn3m	$[P4_{2}/n\ \overline{3}\ 2/m]$	$[Pn\overline{3}m]$	$[P4_{2}/n\ \overline{3}\ 2/m]$	Pn3m (IT ,1952 )
225	$[O_{h}^{5}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right) \!:\!4/\tilde{6}\cdot m]$	Fm3m	$[F4/m\ \overline{3}\ 2/m]$	$[Fm\overline{3}m]$	$[F4/m\ \overline{3}\ 2/m]$	Fm3m (IT, 1952 )
226	$[O_{h}^{6}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right) \!:\!4/\tilde{6}\cdot \tilde{c}]$	Fm3c	$[F4/m\ \overline{3}\ 2/c]$	$[Fm\overline{3}c]$	$[F4/m\ \overline{3}\ 2/c]$	Fm3c (IT, 1952 )
227	$[O_{h}^{7}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a(a\!:\!a)\right):\!4_{1}//\tilde{6}\cdot m]$	Fd3m	$[F4_{1}/d\ \overline{3}\ 2/m]$	$[Fd\overline{3}m]$	$[F4_{1}/d\ \overline{3}\ 2/m]$	Fd3m (IT, 1952 )
228	$[O_{h}^{8}]$	$[\left(\displaystyle{a + c \over 2}\!\bigg/\!{b + c \over 2}\!\bigg/\!{a + b \over 2}\!:\!a\!:\!(a\!:\!a)\right):\!4_{1}//\tilde{6}\cdot \tilde{c}]$	Fd3c	$[F4_{1}/d\ \overline{3}\ 2/c]$	$[Fd\overline{3}c]$	$[F4_{1}/d\ \overline{3}\ 2/c]$	Fd3c (IT, 1952 )
229	$[O_{h}^{9}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!4/\tilde{6}\cdot m]$	Im3m	$[I4/m\ \overline{3}\ 2/m]$	$[Im\overline{3}m]$	$[I4/m\ \overline{3}\ 2/m]$	Im3m (IT, 1952 )
230	$[O_{h}^{10}]$	$[\left(\displaystyle{a + b + c \over 2}\!\bigg/\!a\!:\!(a\!:\!a)\right)\!:\!4_{1}//\tilde{6}\cdot {1 \over 2}\widetilde{abc}]$	Ia3d	$[I4_{1}/a\ \overline{3}\ 2/d]$	$[Ia\overline{3}d]$	$[I4_{1}/a\ \overline{3}\ 2/d]$	Ia3d (IT, 1952 )

^†Abbreviations used in the column Comments: IT, 1952: International Tables for X-ray Crystallography, Vol. 1 (1952)

; Sh–K; Shubnikov & Koptsik (1972)

. Note that this table contains only one notation for the b-unique setting and one notation for the c-unique setting in the monoclinic case, always referring to cell choice 1 of the space-group tables.

Triclinic symbols are unique if the unit cell is primitive. For the standard setting of monoclinic space groups, the lattice symmetry direction is labelled b. From the three possible centrings A, I and C, the latter one is favoured. If glide components occur in the plane perpendicular to [010], the glide direction c is preferred. In the space groups corresponding to the orthorhombic group mm2, the unique direction of the twofold axis is chosen along c. Accordingly, the face centring C is employed for centrings perpendicular to the privileged direction. For space groups with possible A or B centring, the first one is preferred. For groups 222 and mmm, no privileged symmetry direction exists, so the different possibilities of one-face centring can be reduced to C centring by change of the setting. The choices of unit cell and centring type are fixed by the conventional basis in systems with higher symmetry.

When more than one kind of symmetry elements exist in one representative direction, in most cases the choice for the space-group symbol is made in order of decreasing priority: for reflections and glide reflections m, a, b, c, n, d, for proper rotations and screw rotations $[6,\ 6_{1},\ 6_{2},\ 6_{3},\ 6_{4},\ 6_{5}]$ ; $[4,\ 4_{1},\ 4_{2},\ 4_{3}]$ ; $[3,\ 3_{1},\ 3_{2}]$ ; $[2,\ 2_{1}]$ [cf. IT (1952), p. 55, and Chapter 4.1 ].

12.3.5. Systematic absences

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Hermann (1928) emphasized that the short symbols permit the derivation of systematic absences of X-ray reflections caused by the glide/screw parts of the symmetry operations. If $[{\bi H} = (h,k,l)]$ describes the X-ray reflection and $[({\bi W},{\bi w})]$ is the matrix representation of a symmetry operation, the matrix can be expanded as follows: $[({\bi W},{\bi w}) = ({\bi W}, {\bi w}_{g} + {\bf w}_{l}) = ({\bi W},\left(\matrix{\hfill w_{g}^{1}\cr \hfill w_{g}^{2}\cr \hfill w_{g}^{3}\cr}\right) + {\bi w}_{l}).]$ The absence of a reflection is governed by the relation (i) $[{\bi H} \cdot {\bi W} = {\bi H}]$ and the scalar product (ii) $[{\bi H} \cdot {\bi w}_{g} = hw_{g}^{1} + kw_{g}^{2} + lw_{g}^{3}]$ . A reflection H is absent if condition (i) holds and the scalar product (ii) is not an integer. The calculation must be made for all generators and indicators of the short symbol. Systematic absences, introduced by the further symmetry operations generated, are obtained by the combination of the extinction rules derived for the generators and indicators.

Example: Space group $[D_{4}^{10} = I4_{1}22\ (98)]$

The generators of the space group are the integral translations and the centring translation $[(xyz,\textstyle{1\over 2} \textstyle{1\over 2} \textstyle{1\over 2})]$ , the rotation 2 in direction [100]: $[(x\overline{y}{\hbox to .5pt{}}\overline{z},000)]$ and the rotation 2 in direction $[\hbox{[}1\overline{1}0\hbox{]}]$ : $[(\overline{y}{\hbox to .5pt{}}\overline{x}{\hbox to .5pt{}}\overline{z},0 0 -\textstyle{1\over 4})]$ . The operation corresponding to the indicator is the product of the two generators: $[(x\overline{y}{\hbox to .5pt{}}\overline{z}, 000) \ (\overline{y}{\hbox to .5pt{}}\overline{x}{\hbox to .5pt{}}\overline{z}, 0 0 -\textstyle{1\over 4}) = (\overline{y}xz, 00\textstyle{1\over 4}).]$ The integral translations imply no restriction because the scalar product is always an integer. For the centring, condition (i) with $[{\bi W} = {\bi I}]$ holds for all reflections (integral condition), but the scalar product (ii) is an integer only for [h + k + l = 2n] . Thus, reflections hkl with $[h + k + l \ne 2n]$ are absent. The screw rotation 4 has the screw part $[{\bi w}_{g} = (0,0,\textstyle{1\over 4})]$ . Only 00l reflections obey condition (i) (serial extinction). An integral value for the scalar product (ii) requires [l = 4n] . The twofold axes in the directions [100] and $[\hbox{[}1\overline{1}0\hbox{]}]$ do not imply further absences because $[{\bi w}_{g} = {\bf 0}]$ .

12.3.6. Generalized symmetry

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The international symbols can be suitably modified to describe generalized symmetry, e.g. colour groups, which occur when the symmetry operations are combined with changes of physical properties. For the description of antisymmetry (or `black–white' symmetry), the symbols of the Bravais lattices are supplemented by additional letters for centrings accompanied by a change in colour. For symmetry operations that are not translations, a prime is added to the usual symbol if a change of colour takes place. A complete description of the symbols and a detailed list of references are given by Koptsik (1966). The Shubnikov symbols have not been extended to colour symmetry.

References

Bertaut, E. F. (1976). Study of principal subgroups and their general positions in C and I groups of class mmm – D_2h. Acta Cryst. A32, 380–387.Google Scholar

Burzlaff, H. & Zimmermann, H. (1980). On the choice of origins in the description of space groups. Z. Kristallogr. 153, 151–179.Google Scholar

Burzlaff, H. & Zimmermann, H. (2002). On the treatment of settings of space groups and crystal structures by specialized short Hermann–Mauguin space-group symbols. Z. Kristallogr. 217, 135–138.Google Scholar

Hermann, C. (1928). Zur systematischen Strukturtheorie I. Eine neue Raumgruppensymbolik. Z. Kristallogr. 68, 257–287.Google Scholar

Hermann, C. (1929). Zur systematischen Strukturtheorie IV. Untergruppen. Z. Kristallogr. 69, 533–555.Google Scholar

Hermann, C. (1931). Bemerkungen zu der vorstehenden Arbeit von Ch. Mauguin. Z. Kristallogr. 76, 559–561.Google Scholar

International Tables for X-ray Crystallography (1952). Vol. I, edited by N. F. M. Henry & K. Lonsdale. Birmingham: Kynoch Press. [Revised editions: 1965, 1969 and 1977. Abbreviated as IT (1952).]Google Scholar

Koptsik, V. A. (1966). Shubnikov groups. Moscow University Press. (In Russian.)Google Scholar

Shubnikov, A. V. & Koptsik, V. A. (1972). Symmetry in science and art. Moscow: Nauka. (In Russian.) [Engl. transl: New York: Plenum (1974).]Google Scholar

Zimmermann, H. (1976). Ableitung der Raumgruppen aus ihren klassengleichen Untergruppenbeziehungen. Z. Kristallogr. 143, 485–515.Google Scholar

International Tables for Crystallography (2006). Vol. A. ch. 12.3, pp. 823-832
https://doi.org/10.1107/97809553602060000526