键电荷与键共价性之间的关系研究(英文)

Relationship Between Bond Valence andBond Covalency:A Case Study

用一种半经验方法研究了固体材料中键电荷与键共价性的关系．这一理论方法是Ｐｈｉｌｉｐｓ，ＶａｎＶｅｃｈｔｅｎ，Ｌｅｖｉｎｅ，及Ｔａｎａｋａ等人提出的介电描述理论的推广．通过对一个例子ＲＭｎ２Ｏ５（Ｒ＝Ｌａ，Ｐｒ，Ｎｄ，Ｓｍ，Ｅｕ）的研究发现，键电荷越多，所产生的键共价性越大。

The relationship between bond valence and bond covalency has been investigated by a semiempirical method. This semiempirial method is the generalization of the dielectric description theory of Phillips, Van Vechten, Levine and Tanaka schemes. RMn2O5(R = La, Pr, Nd, Sm, Eu) are chosen as an example in order to show the relationship. The results indicate that larger valences usually produce higher bond covalencies. This is in good agreement with the point that the excess charge in the bonding region is the origin of formation of bond covalency.