On the cohesion of covalent structures of elements in condensed phases. I. - cohesion of and bands in a simple Hückel approximation
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چکیده
2014 The cohesion of covalent structures is systematically studied in a simplified Hückel (LCAO) approximation which only allows for one type of interatomic transfer integral for each (03C3 or 03C0) bond. Layers or chains structures with one or two broken 03C3 bonds per atom are compared with saturated or conjugated spn structures. These are also compared with compact metallic sp and with covalent p structures. The overall description is in qualitative agreement with experiment; but cohesive energies are too large and the relative stability of layer and chain structures of tetra, penta and hexavalent elements is too small. LE JOURNAL DE PHYSIQUE TOMF 39, Jt 1’1978, Classification Physics Abstracts 71.00 1
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تاریخ انتشار 2017