Cu+与N-2-羟基-1(S)-甲基-N-甲基甘氨酸间的C-H…Cu(Ⅰ)抓氢键

摘要

采用密度泛函B3LYP (Becke,three-parameter,Lee-Yang-Parr)/6-311G**理论水平研究了Cu+和Cu2+离子与N-[2-羟基-1(S)-甲基]-N-甲基甘氨酸根负离子配体(PT)形成的配合物的结构,重点讨论了配合物中的C-HCu抓氢键结构.计算表明,当单个配体与Cu+结合时,配合物PT…Cu(Ⅰ)结构中有C-HCu抓氢键形成,C-H键伸缩振动频率显著红移,键长显著增大而被活化,配体为三齿配体;当两个配体与Cu2+结合时,配合物PT…Cu(Ⅱ)不存在C-HCu抓氢键结构,配体为双齿配体.NBO及AIM理论分析均表明C-HCu抓氢键属于一种较强的基团间相互作用,在强度和电子行为上与氢键弱相互作用有本质不同.%The structures of the coordination compounds formed between Cu+ , Cu2+ and N-[2-hydroxy-l(S)-methyl]-N-methylglycine anion ligand (PT) anion were investigated by density functional B3LYP (Becke. Three-parameter, Lee-Yang-Parr)/6-311G··theoretical method. The C-Hcu agostic bond structure in the coordination compound (PT···Cu( I )) was discussed. The calculation results showed that the C-Hcu agnostic bond formed when Cu+ coordination binding to only one PT, thereafter, the stretch vibrational frequency of the elongated and activated C-H bond presents a red-shift; and there was no C-Hcu agnostic bond existence when Cu2+ coordination binding with two PTs. Natural bond orbital (NBO) and atoms in molecules (AIM) theories analysis show that the C-Hcu agnostic bond belongs to relative strong interaction between intermolecular groups, and its intensity and electronic behavior are quite different from these of hydrogen bond structures.