InternationalReciprocal spaceTables for Crystallography Volume B Edited by U. Shmueli © International Union of Crystallography 2006 |
International Tables for Crystallography (2006). Vol. B, ch. 3.3, p. 375
## Section 3.3.1.5.4. Representation of surfaces by dots |

Connolly (Langridge *et al*., 1981; Connolly, 1983*a*,*b*) represents surfaces by placing dots on the surface with an approximately uniform superficial density. Connolly's algorithm was developed to display solvent-accessible surfaces of macromolecules and provides for curved concave portions where surface atoms meet. Pearl & Honegger (1983) have developed a similar algorithm, based on a grid, which generates only convex portions which meet in cusps, but is faster to compute than the Connolly surface. Bash *et al.* (1983) have produced a van der Waals surface algorithm fast enough to permit real-time changes to the structure without tearing the surface.

It has become customary to use a dot representation to display computed surfaces, such as the surface at a van der Waals radius from atomic centres, and to use lines to represent experimentally determined surfaces, especially density contours.

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