Criteria for assessing theoretically derived electric field gradient tensor components

Abstract

It is possible to set up an electric field gradient criteria scheme as an aid in assessing the quality of theoretically derived electric field gradient (EFG) tensor components characterized by a non-zero asymmetry parameter. The analysis draws attention to the importance of checking that the theoretically predicted coordinate axes assignments of the principal axes system (PAS) for the EFG tensor components respectively agree with the assignments of the experimental PAS. An application of the PAS-assignment-criterion shows that some well known LCAO MO based EFG approximation schemes when tested on the hydrazoic acid molecule possess a serious limitation, as evidenced by their failure to obey this criterion.