Acta Crystallographica Section A

Foundations of Crystallography

Volume 58, Part 4 (July 2002)

short communications

Acta Cryst. (2002). A58, 410-411 [ doi:10.1107/S0108767302005676 ]

Form factors for core electrons useful for the application of quantum crystallography (QCr) to organic molecules

L. Huang, L. Massa and J. Karle

Abstract: Form factors are calculated for the core electrons of the first-row atoms B, C, N, O and F. The form factors are presented in an analytical form, as appears in International Tables for X-ray Crystallography [Ibers & Hamilton (1974), Vol. IV, pp. 103-145. Birmingham: Kynoch Press; present distributor Kluwer Academic Publishers, Dordrecht]. Having such form factors for the core electrons reduces the number of parameters to be determined by the methods of quantum crystallography (QCr). It is shown that the form factors obtained are quite accurate. Thus, when they are used in QCr, they are expected to be consistent with accurate charge densities.

Keywords: form factors; core electrons; quantum crystallography.