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在B3LYP/6-311++g**、MP2/6-311++g(3df,3pd)及MP2/aug-cc-pvtz水平上分别求得H3SiH…MeHn(Me=Na,Mg,Be;n=1或2)复合物势能面上的3个稳定构型,探讨了以Si-H为电子供体的红移反向氢键相互作用(IHB).经MP2/6-311++g(3df,3pd)水平的计算,在3个复合物中,含基组重叠误差(BSSE)校正的单体间相互作用能分别为-5.98、-8.65和-3.96kJ.mol-1,与MP2/aug-cc-pvtz水平下计算得到的-6.18、-9.12和-4.28kJ·mol-1接近,可见3个反向氢键复合物的相对稳定性顺序为:SiH4...MgH2>SiH4...NaH>SiH4...BeH2.NBO分析及对相关原子化学位移的计算表明,在复合物中,电子流向总体表现为SiH4→MeHn(n=1或2),且直接参与反向氢键形成的H3的化学位移向低场移动.与传统氢键相比,这里Si1-H3既是氢键供体,又是电子供体,从而形成反向氢键相互作用.另外,采用分子中原子理论(AIM)分别对各复合物中相关键鞍点处的电子密度拓扑性质进行了分析,结果表明3个复合物中均存在以静电性质为主的分子间反向氢键弱相互作用.
H3SiH ... MeHn (Me = Na, Mg, Be) was calculated at B3LYP / 6-311 ++ g **, MP2 / 6-311 ++ g (3df, 3pd) and MP2 / aug-cc- n = 1 or 2) complex complex, we discussed the redshift reverse hydrogen bond interaction (IHB) with Si-H as electron donors.After MP2 / 6-311 ++ g (3df, 3pd). The intermolecular interaction energies of the three complexes with BSSE correction were -5.98, -8.65 and -3.96kJ · mol-1, respectively, / aug-cc-pvtz calculated -6.18, -9.12 and -4.28kJ · mol-1 close to the relative stability of the three reverse hydrogen bonds complex sequence: SiH4 ... MgH2> SiH4. ..NaH> SiH4 ... BeH2.NBO The analysis and calculation of the related atomic chemical shifts show that in the complex, the overall electron flow behaves as SiH4 → MeHn (n = 1 or 2) and is directly involved in the reverse hydrogen bond The formation of the chemical shifts of H3 to lower field.Compared with the traditional hydrogen bonds, where Si1-H3 is both a hydrogen bond donor and an electron donor, thus forming an inverse hydrogen bond interaction.In addition, the molecular atomic theory (AIM), the topological properties of the electron density at the relevant saddle point in each complex were analyzed. The results showed that the three complex Was present in both inter-molecular electrostatic properties mainly hydrogen reverse weak interaction.