化学学报 ›› 2016, Vol. 74 ›› Issue (3): 285-292.DOI: 10.6023/A15100641 上一篇    

研究论文

HXeBr与苯和苯的衍生物弱相互作用的理论研究

赵清, 齐博宇, 王宝金, 陈飞武   

  1. 北京科技大学化学与生物工程学院化学与化学工程系 功能分子与晶态材料科学与 应用北京市重点实验室 北京 100083
  • 收稿日期:2015-10-03 出版日期:2016-03-15 发布日期:2015-12-23
  • 通讯作者: 陈飞武 E-mail:chenfeiwu@ustb.edu.cn
  • 基金资助:

    项目受国家自然科学基金(Nos. 21173020, 21473008)资助.

Theoretical Investigation on Weak Interactions of HXeBr with Benzene and Its Derivatives

Zhao Qing, Qi Boyu, Wang Baojin, Chen Feiwu   

  1. Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Beijing 100083
  • Received:2015-10-03 Online:2016-03-15 Published:2015-12-23
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 21173020, 21473008).

采用MP2/aug-cc-pVDZ (对于Xe和I原子采用aug-cc-pVDZ-PP基组)优化了复合物HXeBr…C6H5X (X=H, CH3, NH2, N(CH3)2, NHCH3, OH, OCH3, CN, F, Cl, Br, I, COOH, SO3H, CF3)及单体的几何构型, 详细分析了π…H键和双齿氢键两种弱相互作用类型的特征, 以及不同的取代基对这两种弱相互作用能的影响. 对14个双齿氢键型复合物, 我们发现复合物的相互作用能与苯环衍生物(C6H5X)的偶极矩, 复合物中Xe—Br键键长的变化, H—Xe键键长的变化和H—Xe键振动频率的变化, 以及双齿氢键上Br原子和两个H原子范德华表面相互穿透距离之和均有较好的线性关系. 另外, 我们还发现复合物的相互作用能与双齿氢键上两个键临界点的电子密度之和, 电子密度Laplacian值之和, 静电势之和, 以及双齿氢键和苯环碳原子形成环的环临界点处的电子密度, 电子密度Laplacian值以及静电势均有着较好的线性关系.

关键词: 稀有气体, HXeBr, 苯, π…H键, 双齿氢键

Geometries of complexes HXeBr…C6H5X (X=H, CH3, NH2, N(CH3)2, NHCH3, OH, OCH3, CN, F, Cl, Br, I, COOH, SO3H, CF3) and its monomers are optimized with MP2/aug-cc-pVDZ (aug-cc-pVDZ-PP for Xe and I). The aug-cc-pVDZ-PP is a small core pseudopotential basis set. It ignores 28 electrons for Xe and I atoms. Two types of weak interactions, π…H bond and bifurcated hydrogen bonds, are analyzed in detail. The effects of substituting group of the benzene ring on the weak interaction energies are investigated. Their effects on π…H bond are different from that on bifurcated hydrogen bonds. As for the complexes with π…H bond, electron withdrawing groups reduce the interaction energies while electron donating groups increase the interaction energies. However, for the complexes with bifurcated hydrogen bonds, electron withdrawing groups increase the interaction energies while electron-donating groups decrease the interaction energies. The effects of substituting groups on geometrical parameters of HXeBr are also analyzed. As for 14 complexes of HXeBr…C6H5X with bifurcated hydrogen bonds, it is found that their weak interaction energies have very good linear relationships with dipole moments of C6H5X, bond length changes of Xe—Br and H—Xe bonds, vibrational frequency changes of H—Xe bonds, and the sum of two interpenetration distances of Van der Waals surfaces of bromine and two hydrogen atoms which are connected to the bromine atom by hydrogen bonds. It is also found that the weak interaction energies of 14 complexes above have very good linear relationships with the sum of electron densities (ρ), the sum of ∇2ρ and the sum of electrostatic potentials at two critical points of bifurcated hydrogen bonds, and with the electron density, ∇2ρ and the electrostatic potential at the ring critical point which is inside a ring formed by the bifurcated hydrogen bonds and two carbon atoms of the benzene ring. As for the complexes with bifurcated hydrogen bonds, the weak interaction energies between the monomers can be understood approximately as dipole-dipole interaction.

Key words: rare gas, HXeBr, benzene, π…H bond, bifurcated hydrogen bonds