用HF／3－21G*abinitio法对金属硼化物MB2／MB＋2（M＝Li，Na，Be，Mg，Al）的75个电子态的结构进行了能量梯度法构型优化，再用大基组二次组态相互作用QCISD（T）／6－311G进行单点计算，得到了结构参数和总能量．为了考察各原子簇的稳定性，还对24个碎片的70多个电子态进行优化，并求得相应的QCISD（T）能量，在此基础上计算了原子化能、电高能、离解通道和碎片化能，得到了原子簇的稳定性规律． The structure of 75 electronic states of metal boride MB2 / MB + 2 (M = Li, Na, Be, Mg, Al) was optimized by HF method using HF / 3-21G * abinitio method. The secondary configuration interaction QCISD (T) / 6-311G was calculated by single point, and the structural parameters and total energy were obtained. In order to investigate the stability of each cluster, more than 70 electronic states of 24 fragments were also optimized, and the corresponding QCISD (T) energies were obtained. Based on these calculations, the energies of atomization, electron energies, dissociation channels and Fragmentation energy, the stability of the atomic cluster rules.