A B3LYP and MP2 theoretical investigation on the cooperativity effect between the X-H center dot center dot center dot H-M (X = F, Cl, Br; M = Li, Na, K) dihydrogen-bonding and H-M center dot center dot center dot pi interactions involving C6H6

作者：Li, Bao-hui; Shi, Wen-jing^*; Ren, Fu-de

来源：Computational and Theoretical Chemistry, 2013, 1020: 81-90.

DOI：10.1016/j.comptc.2013.07.026

• Cooperativity effect
• Dihydrogen bond
• H-M center dot center dot center dot pi interaction
• Surface electrostatic potential
• MP2(full)

The DFT-B3LYP/6-311++G(3df,2p) and MP2(full)/6-311++G(3df,2p) calculations were carried out on the binary complex formed by HM (M = Li, Na, K) and XH (X = F, Cl, Br) or C6H6, as well as the ternary system XH center dot center dot center dot HM center dot center dot center dot C6H6. The cooperativity effect between the dihydrogen-bonding and H-M center dot center dot center dot pi interactions was investigated. The result shows that the H center dot center dot center dot H and H-M center dot center dot center dot pi interactions are strengthened in the ternary complex in comparison with those in the corresponding binary system. The cooperativity effect of the dihydrogen bond on the H-M center dot center dot center dot pi interaction is more pronounced than that of the H-M center dot center dot center dot pi interaction on the H center dot center dot center dot H interaction for the ternary system with HNa or HK, while it is contrary in the ternary complex with HLi. Furthermore, the moderate cooperativity effects between the H center dot center dot center dot H and H-M center dot center dot center dot pi interactions exist in the ternary complexes with FH, while the remarkable cooperativity effects are present in those with the partially covalent CIH center dot center dot center dot HM or BrH center dot center dot center dot HM dihydrogen-bonding interaction. Cooperativity effects follow the order of XH center dot center dot center dot HNa center dot center dot center dot C6H6 > XH center dot center dot center dot HLi center dot center dot center dot C6H6 > XH center dot center dot center dot HK center dot center dot center dot C6H6 and CIH center dot center dot center dot HM center dot center dot center dot C6H6 > BrH center dot center dot center dot HM center dot center dot center dot C6H6 > FH center dot center dot center dot HM center dot center dot center dot C6H6. Cooperativity effect was analyzed using the surface electrostatic potentials, electron density shifts and AIM (Atoms in Molecules) methods as well as charges of the hydrogen atoms in H center dot center dot center dot H moiety. Although the same optimized geometry is obtained, the cooperativity energy obtained considering that it comes either from "X-center dot center dot center dot H-2 center dot center dot center dot M+center dot center dot center dot C6H6" or "XH center dot center dot center dot HM center dot center dot center dot C6H6" is different.

• 出版日期2013-9-15
• 单位山西医科大学; 中北大学