ISSN:
1600-5724
Source:
Crystallography Journals Online : IUCR Backfile Archive 1948-2001
Topics:
Chemistry and Pharmacology
,
Geosciences
,
Physics
Notes:
Several simple rules, Rano,4, Rano,5, Rano,6 and Rano,7, have been derived on the basis of the mathematical and physical characteristics of anomalous dispersion experiments that permit the estimation of values for triplet phase invariants. They apply to two-wavelength experiments and concern a variety of values defined in terms of the real and imaginary corrections to atomic scattering factors. The rules apply to the case of a single type of predominant anomalous scatterer. The generalization to more than one type of predominant anomalous scatterer is also described. Test examples show that large numbers of invariants may be evaluated by these means with reliabilities that, in certain circumstances, are at a potentially useful level, but the ultimate applicability depends, of course, on the reliability of the experimental data. The only information required besides the measurements of the diffraction intensities is the chemical composition of the anomalously scattering atoms. If there is more than one type of predominant anomalous scatterer, information concerning the relative proportion of the different types is also required.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1107/S0108767384000799
