Quadrupole coupling constants and isomeric Mossbauer shifts for inorganic compounds and complexes containing elements from period V calculated by ab initio methods

In the present work we report the results of ab initio study, within GAUSSIAN 98, of a large number of halogen, antimony and tin containing molecules and complexes. The calculations were carried out with the use of small and medium basis sets, i.e. 3-21G* (for halogens, antimony and tin) atoms and 6-31G* basis sets (for F, Cl and Br). To demonstrate the quality of the calculations the calculated bond length and quadrupole coupling constant (QCC) were compared with the corresponding experimental values for the compounds studied. With a few exceptions, the overall agreement with experiment is most satisfactory. The calculated NQCC values were used as a test of the quality of the wave functions. The results on Mossbauer chemical shifts are also in a good agreement with the experimental data, however, these quantities were measured only for a few compounds.