<i>Ab initio </i> MO studies of nuclear spin-spin coupling constants in PH<img src='http://www.niscair.res.in/jinfo/two.gif' border=0>, PH₃ and PH<img src='http://www.niscair.res.in/jinfo/plusfour.gif' border=0> systems

Abstract

<i>Ab initio </i> molecular orbital calculations of electron coupled nuclear spin-spin coupling constants are performed for PH<img src='http://www.niscair.res.in/jinfo/two.gif' border=0>, PH₃ and PH<img src='http://www.niscair.res.in/jinfo/plusfour.gif' border=0> systems using the SCF perturbation theory. This study deals with the basis set dependence and relative importance of the major contributing terms such as orbital diamagnetic, orbital paramagnetic, spin dipolar and Fermi contact terms. In all calculations, basis sets have been augmented with bond centered functions or nuclear centered higher angular momentum functions or both. Basis sets having uncontracted <i>'s' </i> functions along with bond centered functions and/or polarization functions predict most of these couplings fairly satisfactorily with their experimental counterparts.