Inverse halogen bonds interactions involving Br in the electronic deficiency systems of CH3+...Br-Y (Y=H, CCH, CN, NC) have been investigated by B3LYP/6- 311++G(d, p) and MP2/6-311++G(d, p) methods. The cal...Inverse halogen bonds interactions involving Br in the electronic deficiency systems of CH3+...Br-Y (Y=H, CCH, CN, NC) have been investigated by B3LYP/6- 311++G(d, p) and MP2/6-311++G(d, p) methods. The calculated interaction energies with basis set super-position error correction of the four IXBs complexes are 218.87, 219.48, 159.18, and 143.05kJ/mol (MP2/6-311++G(d, p)), respectively. The relative stabilities of the four complexes increased in the order: CH3+ … BrCN〈CH3+…- BrNC〈CH3+… BrH≈CH3+ …BrCCH. Natural bond orbital theory analysis and the chemical shifts calculation of the related atoms revealed that the charges flow from Br-Y to CH3e. Here, the Br of Br-Y acts as both a halogen bond donor and an electron donor. Therefore, compared with conventional halogen bonds, the IXBs complexes formed between Br-Y and CH3+. Atoms-in-molecules theory has been used to investigate the topological properties of the critical points of the four IXBs structures which have more covalent content.展开更多
基金This work was supported by the National Natural Science Foundation of China (No.51063006 and No.50975273) and the "QingLan" Talent Engineering Funds of Tianshui Normal University.
文摘Inverse halogen bonds interactions involving Br in the electronic deficiency systems of CH3+...Br-Y (Y=H, CCH, CN, NC) have been investigated by B3LYP/6- 311++G(d, p) and MP2/6-311++G(d, p) methods. The calculated interaction energies with basis set super-position error correction of the four IXBs complexes are 218.87, 219.48, 159.18, and 143.05kJ/mol (MP2/6-311++G(d, p)), respectively. The relative stabilities of the four complexes increased in the order: CH3+ … BrCN〈CH3+…- BrNC〈CH3+… BrH≈CH3+ …BrCCH. Natural bond orbital theory analysis and the chemical shifts calculation of the related atoms revealed that the charges flow from Br-Y to CH3e. Here, the Br of Br-Y acts as both a halogen bond donor and an electron donor. Therefore, compared with conventional halogen bonds, the IXBs complexes formed between Br-Y and CH3+. Atoms-in-molecules theory has been used to investigate the topological properties of the critical points of the four IXBs structures which have more covalent content.