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利用 ＤＶ－ Ｘａ法计算了 ａｒａｃｈｎｏ－（ ＰＨ３）４Ｍ２Ｂ８Ｈ８（μ-Ｈ）２（Ｍ： Ｎｉ，Ｐｄ， Ｐｔ）和 ｃｌｏｓｏ－（ＰＨ３）２ＭＢ１０Ｈ８Ｘ２（ Ｍ： Ｆｅ， Ｒｕ， Ｏｓ； Ｘ： Ｃｌ， Ｂｒ， Ｉ， ＯＨ， Ｌｉ）系列分子的电子结构．结果表明在２类ａｒａｃｈｎｏ－Ｐ４Ｍ２Ｂ８和ｃｌｏｓｏ—ＭＢ１０Ｘ２主干结构中均有类似的２种Ｍ－Ｂ键合：一是金属原子ｄ轨道相对配体原子轨道形成了全对称匹配分子轨道（ＭＯｓ）；二是部分对称性匹配的ＭＯｓ，前者导致Ｍ－Ｂ局域键合较强，而后者相反．在 ａｒａｃｈｎｏ— Ｐ４Ｍ２Ｂ８主体结构中，尽管Ｍ－Ｂ（Ⅱ）键长较Ｍ－Ｂ（Ｉ）短，但是Ｍ－Ｂ（Ⅱ）键几乎无有效的轨道重叠．在ｃｌｏｓｏ－ＭＢ１０Ｘ２中也类似， Ｍ－Ｂ（Ⅱ）有较强的键合强度，而 Ｍ－Ｂ（Ｉ）的计算键级为零．这些原子间距离虽然在合理的键长范围内，但是它们相邻轨道并无共价键合则是少见的现象，也可能由此导致了ａｒａｃｈｎｏ—Ｐ４Ｎｉ２Ｂ８和ｃｌｏｓｏ－（ＰＨ３）２ＭＢ１０Ｈ１０主体结构化合物在合成上的困难．
The molar ratios of arachno- (PH3) 4M2B8H8 (μ-H) 2 (M: Ni, Pd, Pt) and closo- (PH3) 2MB10H8X2 (M: Fe, Ru, Os; X: Cl, Br, I, OH, Li) series of molecular electronic structure. The results showed that there are two similar M-B bonds in the two main groups of arachno-P4M2B8 and closo-MB10X2: one is the symmetry-matching molecular orbitals (MOs) of the metal atom d orbital relative to the ligand orbitals; Is a partial symmetry matching MOs, the former leads to M-B local bond stronger, while the latter is the opposite. In the arachno-P4M2B8 host structure, M-B (II) bonds have virtually no effective orbital overlap despite the shorter M-B (II) bond length than M-B (I) Similarly in closo-MB10X2, M-B (II) has a stronger bond strength and M-B (I) has a calculated bond-level of zero. Although these inter-atomic distances are within a reasonable range of bond lengths, it is not uncommon for their adjacent orbitals to be covalently bonded, potentially resulting in the formation of arachno-P4Ni2B8 and closo- (PH3) 2MB10H10 host structural compounds at Synthetic difficulties.