ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
X-ray and electron elastic scattering factors for He through Ar ground states have been computed from Dirac–Hartree–Fock (DHF) wave functions. Differing from earlier studies, the present DHF wave functions are not restricted to single configurations and will go into the nonrelativistic Hartree–Fock (HF) ground states when the speed of light c ⇒ \infty. The relativistic effects have been analyzed through the differences of scattering factors calculated at DHF and HF levels of theory. It has been found that the effects become stronger as the nuclear charge increases and anomalous behavior observed in the literature for C, N, O, Si, P and S is due to the use of either single- or average-energy multiconfiguration DHF wave functions to extract the relativistic effects for these systems preventing attainment of the correct nonrelativistic limit. Scattering factors of common ions of the first- and second-row elements and the valence state of C and Si are also given.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108767396003960
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