稀土化合物中稀土离子和配位体的成键性质一直是人们注意研究的课题之一,一般认为属于离子键,但具有少量的共价性,然而,具体的数量级尚不清楚。本文利用Phillips,VanVechten和Levine理论,对LaX_3(X=F、Cl、Br、OH)晶体的键性和有关参数进行了具体计算,定量指出了镧离子和配体成键的离子性和共价性程度,比较了各晶体中有关的键参数,发现了和宏观物理现象相关的规律。1 理论公式 Rare earth compounds rare earth ions and ligand bonding properties has been one of the subjects of attention, generally considered to be ionic bonds, but with a small amount of covalent, however, the specific magnitude is not clear. Phillips, VanVechten and Levine theory were used to calculate the bond and related parameters of LaX_3 (X = F, Cl, Br, OH) crystals quantitatively. The ionic and covalent The degree of sexuality is compared with the related key parameters in each crystal, and the laws related to macroscopic physical phenomena are found. 1 theoretical formula