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采用密度泛函B3LYP方法，在6—311＋＋G（d，p）基组水平上对碱（土）金属离子（Li＋,Na＋，K＋，Be2＋，Mg2＋和Ca2＋）与2-（3’-羟基-2’-吡啶基）苯并噁唑（HPyBO）的36种阳离子-π复合物的初始构型进行了几何全优化，并计算了其相互作用能．结果表明，碱（土）金属离子与HPyBO复合物有较强的阳离子-π相互作用，部分复合物甚至达到了化学键的强度．相对能量的变化表明碱（土）金属离子的作用能改变HPyBO分子内质子转移过程的能垒，甚至可以导致优势构型反转．当考虑水的溶剂效应后，各质子转移异构体的相对能量及质子转移的能垒均有一定程度的改变．另外，应用分子中的原子（AIM）方法对复合物分子内氢键的键临界点性质进行了分析．“,”The structures of 2-（3＇-hydroxy-2＇-pyridyl）benzoxazole （HPyBO） with alkali （or alkaline earth） metal ions （Li＋, Na＋, K＋, Be2＋, Mg2＋ and Ca2＋） were fully optimized at the 6-311 ＋ ＋G（d,p） level by using B3LYP density functional theory and the binding energies were calculated at the same level. The result shows that the cation-n interaction between alkali （or alkaline earth） metal ions and HPyBO complexes are very strong, some of the interactions are even comparable to chemical bonding. The relative energies show that cation-n interaction can change the energy barrier of intramolecular proton transfer. When considering the solvent effect of water, the relative energies of isomers and the energy barrier of intramolecular proton transfer are changed to some extent. In addition, the properties at the BCPs （bond critical points） of intramolecular hydrogen bond in the complexes are also discussed.