A theoretical analysis of the weakly bound complexes HM ··· HXY (M=O and S; XY=CN and NC): comparison with H₂M ··· HXY complexes

Abstract

An ab initio study of the complexes formed between MH (M=O and S) and HXY (XY=CN and NC) was carried out at the UQCISD/6-311++G(2df,2p) level. For comparison, the corresponding H₂M–HXY complexes were also studied. Two minima were found for each molecular pair. The results show the necessity of electron correlation and larger basis sets in the study of open-shell hydrogen-bonded complexes. As the proton donor and acceptor, the OH radical is favourable for the formation of a hydrogen bond with HXY than is the SH radical. The MH radical is more likely to donate a proton than H₂M, whereas H₂M is more likely to accept a proton than the MH radical. Natural bond orbital and atoms in molecules analyses were performed for these systems. It is shown that the complexes are held together mainly by electrostatic interactions.

Keywords:

• ab initio
• electronic structure
• quantum chemistry
• computational chemistry

Acknowledgements

This work was supported by the National Natural Science Foundation of China (grant No. 20973149) and the Scientific and Technological Innovation Fund for College Students, Yantai University, China. It was also supported, in part, by open project of the State Key Laboratory of Supramolecular Structure and Materials (SKLSSM200909), Jilin University, China.

Notes

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