硝酸羟胺-(H_2O)_n复合物氢键相互作用的密度泛函研究

为研究硝酸羟胺-(H_2O)_n复合物的氢键作用,采用密度泛函B3LYP方法在6-311++G(d, p)基组水平上对硝酸羟胺-(H_2O)_n复合物的结构进行优化,采用MP2/6-311++G(d, p)方法,经基组叠加误差和零点能校正计算得到复合物的相互作用能.利用自然键轨道分析方法研究复合物氢键作用的本质,并对复合物中水分子的振动光谱进行分析.计算结果表明,硝酸羟胺-(H_2O)_n复合物存在着6个硝酸羟胺-H_2O稳定构型和8个硝酸羟胺-(H_2O)_2稳定构型,且最稳定构型的相互作用能分别为52.821 kJ·mol~(-1)和73.349 kJ·mol~(-1).在硝酸羟胺-(H_2O)_n复合物中,水中H-O伸缩振动频率明显红移,且红移增大的程度与复合物稳定化能的变化趋势基本一致.

Density Functional Theory Study on Hydrogen Bonding Interaction of Hydroxylamine Nitrate-(H2O)n

In order to study the hydrogen bonding interaction of hydroxylamine nitrate-(H2O)n complexes, density functional theory B3LYP/6-311++G(d, p) was employed to obtain the optimized geometries of the hydroxylamine nitrate-(H2O)n complexes. MP2/6-311++G (d, p) was used to calculate the intermolecular interaction energy with basis set superposition error correction and zero point energy correction. The nature of hydrogen bond was studied by means of natural bond orbital analysis, and the vibration spectrum of the water molecule in the complex was analyzed. 6 hydroxylamine nitrate-H2O configurations and 8 hydroxylamine nitrate-(H2O)2 configurations have been obtained respectively. The corresponding interaction energies of the most stable hydroxylamine nitrate-H2O and hydroxylamine nitrate-(H2O)2 are 52.821kJ·mol-1 and 73.349kJ·mol-1. There are large red-shifts for the symmetric H-O stretching vibrational frequencies of water in the hydroxylamine nitrate-(H2O)n complexes, the degree of red-shift increasing is consistent with the variation trend of stabilization energy.