Crystal-field potential for a substitutional impurity in monoatomic molecular cryocrystals

An expression is derived for the crystal field of nearest neighbors in the vicinity of a site in static monoatomic fcc and hcp lattices in the approximation of atom–atom central potentials of the power-law type. The results obtained are employed to calculate the crystal-field potential for rotational motion of diatomic homo- and heteronuclear substitutional impurities. The numerical calculations were performed using the constants for the Lennard-Jones atom–atom interaction for nitrogen and carbon monoxide impurities in argon and krypton matrices.