Nh. Hu et Ys. Liu, ESTIMATION OF THE ONE-PHASE STRUCTURE SEMINVARIANTS IN THE SINGLE ISOMORPHOUS REPLACEMENT CASE - AN APPLICATION OF HAUPTMANS DISTRIBUTION, Acta crystallographica. Section A, Foundations of crystallography, 51, 1995, pp. 520-524
A method for estimating the one-phase structure seminvariants (OPSSs)
having values of 0 or pi has been proposed on the basis of the probabi
listic theory of the three-phase structure invariants for a pair of is
omorphous structures [Hauptman (1982). Acta Cryst. A38, 289-294]. The
test calculations using error-free diffraction data of protein cytochr
ome c(550) and its PtCl42- derivative show that reliable estimates of
a number of the OPSSs can be obtained. The reliability of the estimati
on increases with the increase of the differences between diffraction
intensities of the native protein and its heavy-atom derivative. A mea
ns to estimate the parameters of the distribution from the diffraction
ratio is suggested.