Calculation of the Cohesive Energy of Zincblende

Abstract

The cohesive energy of zincblende has been calculated quantum mechanically by introducing a covalency correction into the usual pure ionic binding. The cohesive energy per ion-pair thus obtained is 1.46 in atomic unit which is very near the observed value 1.36 derived by means of Born-Harber's energy cycle, and is certainly greater than the value calculated for purely ionic binding by about 60%. This method of calculation would be generally applicable not only for sphalerite-type crystals but also for wurzite-type ones.