Cooperativity between two types of hydrogen bond in H(3)C-HCN-HCN and H(3)C-HNC-HNC complexes.
Hydrogen-bonded clusters, H(3)C-HCN, HCN-HCN, H(3)C-HCN-HCN, H(3)C-HNC, HNC-HNC, and H(3)C-HNC-HNC, have been studied by using ab initio calculations. The optimized structures, harmonic vibrational frequencies, and interaction energies are calculated at the MP2 level with aug-cc-pVTZ basis set. The cooperative effects in the properties of these complexes are investigated quantitatively. A cooperativity contribution of around 10% relative to the total interaction energy was found in the H(3)C-HCN-HCN complex. In the case of H(3)C-HNC-HNC complex, the cooperativity contribution is about 15%. The cooperativity contribution in the single-electron hydrogen bond is larger than that in the hydrogen bond of HCN-HCN and HNC-HNC complexes. NMR chemical shifts, charge transfers, and topological parameters also support such conclusions.
Li
Qingzhong
Q
Science and Engineering College of Chemistry and Biology, Yantai University, Yantai, PR China. lqz02@mails.tsinghua.edu.cn
An
Xiulin
X
Luan
Feng
F
Li
Wenzuo
W
Gong
Baoan
B
Cheng
Jianbo
J
Sun
Jiazhong
J