摘要
采用密度泛函理论,在B3LYP/6-311+G^(**)水平上对C_3N_3(NH_2)_3、[C(O)NH]_3、H_2O 3种单体在气相中形成的双分子氢键作用体系进行构型优化和频率计算。通过几何优化得到一系列含多个氢键的复合物。频率分析表明,与单体相比,体系形成氢键作用后,参与氢键形成相关的键的红外谱带位置和振动强度都发生明显的变化,其中C_3N_3(NH_2)_3-[C(O)NH]_3体系中N8—H9键的红移最明显。同时,通过B3LYP/6-311+G^(**)和MP2/6-311+G^(**)水平计算的含基组重叠误差(BSSE)校正的氢键相互作用能分析表明,C_3N_3(NH_2)_3-[C(O)NH]_3氢键体系的相互作用能最大,其次是([C(O)NH]_2)_2体系,采用MP2/6-311+G^(**)方法计算的相互作用能分别达到-14.171 kcal·mol^(-1)和-10.217 kcal·mol^(-1)。另外,通过自然键轨道理论揭示氢键相互作用的本质。
Dimolecular hydrogen-bond interactions between selves and each others among melamine, cyanuric acid and water have been theoretical studied by using density functional theory （DFT） at the B3LYP/6-31 1＋G＊＊ level. A series of complexes with two or more hydrogen bonds were obtained. Some apparently red shifts were found in the vibration analysis resulting from the formation of the hydrogen bonds. The most obvious red shift belongs to the vibration of N8-H9 of C3N3（NH2）3-[C（O）NH]3 hydrogen-bonded complex. We also found that the hydrogen bond interaction energy of C3N3（NH2）3-[C（O）NH]3 was high to -14.171 kcal.mol^-1, and that of the （[C（O）NH]3）2 was -10.217 kcal.mol^-1, which were calculated with basis set superposition error （BSSE） correction at MP2/6-311 ＋G＊＊ level. In addition, natural bond orbital （NBO） analysis was performed to reveal the origin of the hydrogen-bond interation.
出处
《计算机与应用化学》
CAS
CSCD
北大核心
2010年第9期1235-1241,共7页
Computers and Applied Chemistry
