RADIAL-DISTRIBUTION STUDIES UNDER HIGHLY CONSTRAINED CONDITIONS

The consequences of limited scattering data are considered for the determination of radial distribution functions. Such considerations are important, e. g. , when substances are held at extreme pressure in a pressure vessel like the diamond anvil cell. By means of formal relations, alternatives to the direct Fourier inversion of the scattering data are considered, but it is found that they do not usefully circumvent the problems resulting from the truncation of data. Using an ideal set of data, five numerical procedures for inverting the data are compared as a function of the degree of data limitation. An extended-integral method is found to be the most reliable.