Superexchange Interaction Between Magnetic Ion Pairs and Super Transferred Hyperfine Interaction in Weakly Covalent Crystals

摘要

The Dirac-Van Vleck-Serber's method of configuration interaction is extended and systematized in order to handle the interaction between transition metal ions. Specific applications are made to the following problems: (i) Exchange interaction between nearest V(2+) neighbors in KMgF3 (collinear superexchange); (ii) Exchange interaction between nearest V(2+) neighbors in MgO (right angle superexchange); (iii) Superexchange interaction between next nearest V(2+) and Ni(2+) neighbors in MgO (exchange between inequivalent ions). The change in hyperfine field at a magnetic cation site due to cation - cation interaction is also calculated.