Ab initio study of the force constants of inorganic molecules ONF and NF3 |
| |
Authors: | Wolfgang Sawodny Péter Pulay |
| |
Affiliation: | University of Ulm, Department of Inorganic Chemistry, Germany;Central Research Institute for Chemistry of the Hungarian Academy of Sciences, Budapest, Hungary |
| |
Abstract: | The force constants of ONF and NF3 have been determined from Hartree-Fock ab initio wavefunctions by the force method. Three different Gaussian basis sets, ranging from 7s3p augmented with functions on the bonds to 5s2p, were used for ONF. Only the smallest basis was applied to NF3. The results show remarkable agreement with experiment, especially for the coupling constants. The NF stretching force constant is greatly overestimated in calculations with the 5s2p basis. The calculated force field makes it possible to exclude sets of force constants which are unphysical but compatible with the experimental data. The results show that even calculations with 5s2p basis sets can contribute to the determination of force fields.The experimental value of the coupling constant in ONF ranges between 0.27 and 0.54 mdyn; our calculations corroborate the higher value. An estimation of the calculated molecular geometries is given. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|