Evaluation of Van der Waals dipole-dipole and dipole-quadrupole energies and crystal energies in copper,silver and thallium halides

摘要

The Slater-Kirkwood variational method is applied to estimate the Van der Waals dipole-dipole(vdw)and dipole-quadrupole co-efficients for ion-pair interaction in copper,silver and thallium halide crystals.In the analysis of crystal binding based on the interionic force model,the contributions arising from the vdw dipole-dipole and dipole-quadrupole interactions and the short-range repulsive interactions of the type of Born-Mayer,Hellmann and Ali-Hasan have been taken into account.The calculated values of the crystal energy using the Ali-Hasan repulsive potential agree closely with the experimental value.