CALCULATION OF THE ELASTIC PROPERTIES OF CUCL

The elastic constants of CuCl with zinc-blende structure are calculate d by means of two professes, By using, first 3 classical bond-orbital model based on the tight-binding method, and secondly, an approach whi ch combines the latter model with an adjusted empirical pseudopotentia l method. The bond length d, bond polarity alpha(pt), bulk modulus B, elastic shear constants (C-11-C-12)/2, bond-stretching force constant alpha, bond-bending force constant beta, internal displacement paramet er xi effective atomic charge Z, transfer parameter beta*, transverse charge e(T), and piezoelectric charge e(p)* are calculated with both methods. The results are compared with previous theoretical estimates and experiments. (C) 1997 Elsevier Science B.V.