ABSTRACT
The interpretation of the magnetochemical studies of the molecular structure significantly depends on the extent to which the additive principle relating molecular properties to the properties of individual atoms, bonds, and fragments is applicable to the anisotropic magnetic susceptibilities. This principle is definitely valid for average magnetic susceptibilities. These average magnetic susceptibilities were among the first properties to indicate that the molecular characteristics could be equated to the sum of atomic or group contributions. In the tensor additive scheme there is always a parameter of one of the bonds whose value must be introduced arbitrarily or determined independently. The calculation of anisotropic susceptibilities of chemical bonds and atomic groups is carried out by substracting the sum of contributions of all bonds with familiar properties from molecular tensor. In crystals electronic shells of ions are deformed and redistributed between anions and cations because of partially covalent interactions and mutual electrostatic influences.
