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International
Tables for Crystallography Volume C Mathematical, physical and chemical tables Edited by E. Prince © International Union of Crystallography 2006 |
International Tables for Crystallography (2006). Vol. C. ch. 4.2, p. 202
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In addition to the Jena measurements noted above, a number of characteristic X-ray lines were measured on the optically based scale at NBS/NIST. The set of directly measured reference wavelengths is given in Table 4.2.2.1![[link]](/graphics/greenarr.gif)
in bold type. Most of the originally published (NBS/NIST) values were burdened by the 1.8 × 10−6 error in the silicon lattice period, as noted above. These have been corrected in the numerical results summarized in the table. The directly measured elements and lines appearing in this table were often chosen to meet the need for specific reference values in locations near those of certain optical transitions in highly charged ion spectra or spectra from pionic atoms. In addition, early NBS measurements specifically addressed the lines most often used in crystallography and the W Kα transition. In response to the needs of electron spectroscopy, Al and Mg K spectra were also determined (Schweppe, Deslattes, Mooney & Powell, 1994). In this case, the original lattice error had been previously recognized, so that no rescaling was required. The remaining directly measured entries were obtained as opportunities to do so emerged.
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![[K\alpha _2]](/teximages/cbch4o2/cbch4o2fi195.svg)
![[K\alpha _1]](/teximages/cbch4o2/cbch4o2fi196.svg)
![[K\beta _3]](/teximages/cbch4o2/cbch4o2fi197.svg)
![[K\beta _1]](/teximages/cbch4o2/cbch4o2fi198.svg)
The optically based data set was expanded by noting that several groups of accurate (relative) measurements in the literature either contained one of the directly measured lines (bold type) in Table 4.2.2.1 or were explicitly connected to one of them. Most often this situation was realized in reports that indicated a specific reference value, i.e. where it was stated numerical values are based on a scale where, for example, the wavelength of Mo ![[K\alpha _{1}]](/teximages/cbch4o2/cbch4o2fi191.svg)
was taken as 707.831 xu. In such cases, and where other indicators of good measurement quality are presented, it is easy to re-scale the data reported so that it is consistent with the optically based data. This procedure was followed for important groups of measurements from earlier work by Bearden and co-workers, and from the X-ray laboratory at Uppsala. The rescaled numerical results are included in Table 4.2.2.1 in normal type along with the specific literature citations. The indicated uncertainties are standard uncertainties as defined by ISO (Taylor & Kuyatt, 1994; Schwarzenbach, Abrahams, Flack, Prince & Wilson, 1995).
References
Barreau, G. H., Börner, H. G., Egidy, T. V. & Hoff, R. W. (1982). Precision measurement of X-ray energies, natural widths and intensities in the actinide region. Z. Phys. A308, 209–213.Google Scholar
Bearden, J. A. (1967). X-ray wavelengths. Rev. Mod. Phys. 39, 78–100.Google Scholar
Borchert, G. L. (1976). Precise energies of K-Röntgen-lines of Tm, Th, U and Pu. Z. Naturforsch. Teil A, 31, 102–104.Google Scholar
Borchert, G. L., Hansen, P. G., Jonson, B., Ravn, H. L. & Desclaux, J. P. (1980). Comparison of the K X-ray energy ratios of high Z and low Z elements with relativistic SCF DF calculations. Atomic masses and fundamental constants, edited by J. E. Nolen & W. Benenson, Vol. 6, pp. 189–201. New York: Plenum Press.Google Scholar
Deslattes, R. D. & Kessler, E. G. Jr (1985). Experimental evaluation of inner-vacancy level energies for comparison with theory. Atomic inner-shell physics, edited by B. Crasemann, pp. 181–235. New York: Plenum.Google Scholar
Hölzer, G., Fritsch, M., Deutsch, M., Härtwig, J. & Förster, E. (1997). Kα1,2 and Kβ1,3 X-ray emission lines of the 3d transition metals. Phys. Rev. A, 56, 4554–4568.Google Scholar
Mooney, T. M. (1996). Personal communication.Google Scholar
Schwarzenbach, D., Abrahams, S. C., Flack, H. D., Prince, E. & Wilson, A. J. C. (1995). Statistical descriptors in crystallography. II. Report of a Working Group on Expression of Uncertainty in Measurement. Acta Cryst. A51, 565–569.Google Scholar
Schweppe, J., Deslattes, R. D., Mooney, T. & Powell, C. J. (1994). Accurate measurement of Mg and Al Kα1,2 X-ray energy profiles. J. Electron Spectrosc. Relat. Phenom. 67, 463–478.Google Scholar
Schweppe, J. E. (1995). Personal communication.Google Scholar
Taylor, B. N. & Kuyatt, C. E. (1994). Guidelines for evaluating and expressing the uncertainty of NIST measurement results. NIST Technical Note No. 1297. Gaithersburg, MD: National Institute of Standards and Technology.Google Scholar
