丝氨酸与水相互作用的量子化学研究

Quantum Chemistry Calculation of the Interaction Between Serine and H_2O

在密度泛函B3LYP/6-311++G(d,p)水平上对丝氨酸分子与水分子的氢键体系进行了研究,得到6种可能存在的构型.用完全均衡方法对基函数重叠误差进行了校正,计算了分子间的相互作用能.结果表明,H2O与丝氨酸分子中的—OH,—COOH中的—OH以及与—NH2相连的C上的H形成的3个氢键结构的稳定性最强.电子密度拓扑分析结果表明,丝氨酸与水分子间的作用以静电作用为主,较强的化学键具有较强的离子性.

The structures of hydrogen-bonded complexes between serine and H2O are investigated using density functional theory B3LYP method at 6-311＋＋G（d,p） level.The interaction energies of the hydrogen-bonded complexes are calculated,the basis set superposition error（BSSE） correction is considered.Six structures of the serine and H2O complex are finally obtained.Among these six complexes,the three hydrogen bonds which are formed among the H2O,the —OH of serine member,—OH of —COOH and the H atom of CH2 which link to —NH2 is the strongest.The topological analysis of electron density shows that the interaction between serine and H2O are ionic.The stronger of the chemical bond,the prominent of the ionic character is.