Zur Berechnung von mittleren Schwingungsamplituden

Abstract

Some rules for mean amplitudes of vibration u are given. It is shown that the u values for bonded atoms can be calculated by a simple formula needing only stretching force constants and atomic masses. The values obtained for a number of XY3(C3v) and XY4(Td) molecules show generally less than 5% difference from the rigorously calculated ones. The data published in the literature are often several times too large. For the XY3(C3v) molecules a normal coordinate analysis in a M.V.F.F. approximation is given. From a new simple L matrix approximation method mean amplitudes of vibration have been calculated for these species which also agree very well with rigorously calculated ones.