Zero-field splitting calculations. Part I. Evaluation of possible perturbation mechanisms for the Mn2+ ion in an axial crystalline electric field

Abstract

The contributions to the zero-field splitting parameter D for an axial crystalline electric field for Mn2+ (site I) in La2Mg3(NO3)12∙24H2O have been calculated from the known and new perturbation mechanisms up to and including fourth order, using the relativistic wave functions. It is shown that the largest contribution to the observed value of D is due to the second-order perturbation mechanism, in agreement with the prediction of van Heuvelen.