Second-Order Many-Body Perturbation Study of Solid Hydrogen Fluoride†

Abstract

A linear-scaling, local-basis, electron-correlation method based on a truncated many-body expansion of energies has been applied to crystalline hydrogen fluoride in three dimensions. The energies, equilibrium atomic positions, lattice constants, and dipole moments of the two structures (polar and nonpolar) have been determined, taking account of one- and two-body Coulomb (electrostatic), exchange, and correlation interactions exactly and three-body and higher-order Coulomb interactions approximately within certain truncation radii. The longer-range two-body Coulomb interactions are also included to an infinite distance by computing the Madelung constant. The second-order Møller-Plesset perturbation method has been used in conjunction with the aug-cc-pVDZ and aug-cc-pVTZ basis sets for correlation. Counterpoise corrections of the basis-set superposition errors have also been made. Predicted relative energies show that the nonpolar arrangement is considerably more stable than the polar one, establishing the precise three-dimensional structure of this crystal and finally resolving the controversy. The computed lattice constants of the nonpolar configuration agree with the observed to within 0.3 A.