晶体结合的解析模型

Andytical Model for Crystalline Cohesion

简要总结了原子间相互作用的对势和三体势的各种解析模型，进而提出能够统一描述惰性气体分子晶体的结合和卤盐离子晶体的结合的一种新模型。在此模型中，正负离子被想像为“带净电荷的惰性原子”，离子间相互作用势被假设为净电荷之间的Ｃｏｕｌｏｍｂ势，相应的惰性原子的Ｌｅｎｎａｒｄ－Ｊｏｎｅｓ势和Ｂｒｕｃｈ－ＭｃＧｅｅ三体极化─—交换势之和，根据此模型对ＫＣｌ晶体的计算结果与实验基本符合。

A variety of analytical models of pairwise potentials and three-body po-tentials for describing interatomic interactions are briefly reviewed at first.We propose a newcohesion model which is a unified description for both inert-gas solids and alkali halide crys-tals. In the new model,cations and anions are imagined as″ inert-atoms with net charges″. Theinterionic interaction is assumed to be the summation of the Coulomb electrostatic potentialbetween net charges,the Lennard-Jones potential between inert-parts and the Bruch-McGeethree-body potential contributed by nearest-neighbour triple-ion cluster. Calculation resultsof KCl crystal using the present model are basically in agreement with experimental data.