【作者】 刘和秀；

【导师】 满瑞林；

【作者基本信息】 中南大学 ， 化学工程与技术， 2014， 博士

【摘要】 摘要：近年来,尽管分子间相互作用的研究已经取得了突飞猛进的发展,但是不同分子间二体和三体相互作用的氢键和卤键研究依然存在空白,而且卤键与氢键之间的协同性研究也还不够深入。因此,本文采用二阶微扰理论(MP2)从头算法对卤、硫、氮族化合物分子间相互作用的二体和三体的几何构型、相互作用能、卤键与氢键之间以及氢键之间的协同性进行了理论研究,并通过静电势分析和分子中的原子(AIM)分析对这些分子间相互作用的本质进行了探讨。本文得到的结论不仅可以丰富分子间相互作用卤键和氢键的理论知识,而且可以为这些分子间相互作用的实验研究和在相关领域的应用起到推动作用。具体研究内容如下：1.在aug-cc-pVDZ水平对(HCl/HBr)n和BrX(X=F,Cl,Br;n:1;2)分子间相互作用进行了理论计算,并得到以下结论：在HCl/HBr…BrX二体中存在氢键,卤键,非正常氢键和非正常卤键四种稳定的几何构型。对于正常键,其相互作用能随着X原子电负性的增加而增加；而对于非正常键,其相互作用能随着X原子电负性的增加而下降。HCl/HBr和BrX分子表面的静电势分析可以很好地解释这些相互作用特征。三体化合物(HCl/HBr)2…BrX的几何构型和相互作用能计算结果表明：分子结构的稳定性取决于三体结构的类型、形成的氢键和卤键的相对强度以及非正常键的数量；协同能和协同贡献(协同能占总能量的百分比)的大小均说明协同性在这些三体化合物的形成过程中起着非常重要的作用；AIM分析结果表明所有三体化合物的分子间相互作用均属于静电(闭壳型)相互作用。2.在aug-cc-pVTZ水平对HX…(BrCl)n(X=F,Cl,Br;n=1;2)体系进行了理论研究。计算结果表明：二体HX…BrCl的几何构型、相互作用能和分子表面的静电势分析结果表明HBr作为卤键供体可以形成最强的卤键作用,而HF作为氢键供体可以形成最强的氢键作用。三体化合物的研究结果表明：卤原子的电负性越强,三体化合物的相互作用能越大,相应的几何结构越稳定；影响不同构型稳定性的主要因素有卤键和氢键的强度以及HX和两个BrCl分子间的相互作用方式；三体结构协同贡献的绝对值在0.86～15.31%的范围内；AIM分析结果表明这些分子间相互作用都是静电相互作用。3.在aug-cc-pVTZ水平对HX和H2Y的单体、二体HX…H2Y,三体H2Y…HX…H2Y和HX…H2Y…HX(X=F,C1,Br;Y=O,S,Se)进行了理论计算。计算结果表明：复合物的稳定性与X和Y原子的电负性直接相关——电负性越强,相应的复合物越稳定；三体复合物中所有不同氢键之间存在正协同性,协同贡献在14.59～21.26%的范围内,可见协同性在这些三体相互作用中发挥着至关重要的作用；AIM分析结果表明绝大部分相互作用是典型的闭壳型作用；而H2O…HF…H20,H2O…HBr…H20和HF…H2O…HF中的H…O键是介于开壳型和闭壳型之间的靠局域电荷浓度稳定的相互作用。4.在aug-cc-pVTZ水平研究了F/C1取代对HX和H2Y(X=.F,Cl,Br; Y=O,S,Se)之间相互作用的几何构型、相互作用能和协同性的影响。结果表明复合物的结构参数和相互作用能与X原子的电负性直接相关；由于F/C1取代改变了H2Y分子的静电势分布,进而引起了三体分子间相互作用方式的改变,在两种类型的三体中均存在(a)、(b)两种结构；三体化合物的相互作用之间存在正协同性,HX…HFY…HX和HX…HClY…HX的协同贡献的值分别在18.19～23.45%和11.27～22.03%的范围内,而HFY…HX…HFY/HClY…HX…HClY的协同贡献分别在12.87～20.17%和12.09～21.33%的范围内；AIM分析结果表明所有三体中的分子间相互作用都是闭壳型作用。5.结合近年来由C02引起的气候变暖已成为全球最关注的环境问题,选取氯阴离子(C1-)、胍盐阳离子((NH2)3C+)和CO2气体分子体系进行了量子化学计算及分子动力学模拟,以期为设计开发新型高吸收性能的胍盐离子液体提供理论依据。通过对胍盐离子液体的结构特征及胍盐离子液体捕获C02分子的机理进行探讨,结果发现胍阳离子与氯负离子之间的存在较强的相互作用,相互作用能为100kcal/mol左右；它们之间的几何构型以Middle作用模式为主；CO2气体溶解在胍盐离子液体的空隙中,不会对离子对的结构产生明显的影响。图35幅,表37个,参考文献252篇。更多还原

【Abstract】 Abstract:Although the research on the intermolecular interaction has been developed by leaps and bounds in recent years, there is still a blank in the investigation on hydrogen bond and haogen bond in the dimer and trimer between different molecules, and the study on the cooperativity of halogen bond and hydrogen bond is not deep enough, too. Consequently, the theoretical investigations on geometric configuration, interaction energy and the cooperativity in hydrogen bonds or between hydrogen bond and halogen bond in halogen, chalcogen and nitrogen complexes have been carried out with the second order perturbation theory (MP2) method in this paper. The natures of the intermolecular interaction are discussed through the electrostatic analysis and "atoms in molecules"(AIM) analysis. The conclusions in this paper can not only enrich the theoretical knowledge of halogen bond and hydrogen bond, but can promot the experiment researches and applications in related fields of them. The concrete research contents are as follows:1. The theoretical computations are carried out on the intermolecular interactions between (HCl/HBr)n and BrX (X=F, Cl, Br; n=1,2) with aug-cc-pVDZ basis set. The following conclusions are obtained. There are four types of interactions between HC1and BrX which are hydrogen bond, halogen bond, unusual hydrogen bond and unusual halogen bond, respectively. The interaction energies of usual bonds increase with the increase of the electronegativity of X atoms. The interaction energies of unusual bonds decline with the increase of the electronegativity of X atoms. These characteristics can be explained by the electrostatic distribution on the surface of HCl/HBr and BrX molecules. The computational conclusions of geometric structures and interaction energies of the trimers show that the stability of molecular structure depends on the type of trimer’s structure, the relative strength of the hydrogen bond and hydrogen bond, and the number of the unusual bonds. The values of the cooperative energies and the synergetic contributions all demonstrate that the cooperativity plays an important role in the formation process of these three-body compounds. The absolute values of cooperative contribution are in the range of0.80%to21.59%. The conclusions of AIM analysis indicate that the electrostatic (closed-shell) interactions occupy a dominant position in these compounds.2. The theoretical investigations are carried out on the HX--(BrCl)n (X=F, Cl, Br; n=1;2) system with aug-cc-pVTZ basis set. The results of the structural parameters, interaction energies and electrostatic potentials on the molecular surfaces of HX and BrCl suggest that HBr can form the strongest halogen bond acting as donor of halogen bond, while HF can form the strongest hydrogen bond acting as donor of hydrogen bond. The research results of the trimers showed that the stronger the electronegativity of halogen atom is, the more stable the trimer is. The factors of affecting the stability of different configurations are the strength of the halogen and hydrogen bond and the mode of intermolecular interactions between HX and two BrCl. The absolute values of cooperative contributions in trimers are in the range of0.86%～15.31%. The AIM analysis demonstrates that these intermolecule interactions are electrostatic interaction in essential.3. The theoretical computations have been carried out for the monomers, dimers (HX-H2Y) and trimers (H2Y…HX…H2Y, H2Y…HX…H2Y) between HX and H2Y with aug-cc-pVTZ basis. According to the calculation results, the stability of the compound has direct contact with the electronegativity of X and Y atom. The stronger the electronegativity of negatively charged atom is, the greater the stability of the corresponding compound is. The positive cooperativities are found between the different hydrogen bonds in all three-body complexes. Cooperative contributions are in the range of14.59-21.26%, indicating that the cooperativites in these complexes are highly significant. The conclusions of AIM analysis demonstrate most of the intermolecular interactions are typical closed-shell interactions. However, the H…O bonds in H2O…HF…H2O, H2O…HBr…H2O and HF…H2O…HF are stabilized by local charge concentration which is between the closed-shell and opened-shell interactions.4. Theoretical investigation about the influences of F/Cl substitution on the geometries, energies and cooperativites of intermolecular interactions between HX and H2Y are investigated with aug-cc-pVTZ basis set. The conclusions demonstrate that the structural parameters and stabilities of all complexes are directly related to the electronegativity of X atom. The favorable cooperativities are observed in diffeent intermolecular interaction of three-body complexes. The cooperative contributions of HX…FY…HX and HX…HClY…HX exist in the ranges of18.19～23.45%and11.27～22.03%respectively, while the cooperative contributions of HFY…FX…HFY and HCl1Y…HX…HClY are in the ranges of12.87～20.17%and12.09～21.33%. AIM analyses indicate that these compounds are closed-shell interactions.5. Aiming at the environmental issues on which world focus in recent years-the climate warming, the chlorine anion (Cl-), guanidine salt cations ((NH2)3C+) and CO2gas molecule system is selected on which the quantum chemical calculation and molecular dynamics simulation has been carried, providing theoretical foundations for designing and developing new guanidinium ionic liquids with high absorption performance. The structure characteristics of guanidinium ionic liquids and the mechanism of guanidinium ionic liquids capturing CO2molecular are discussed. The strong interactions are found between guanidine cation and chlorine anion, whose interaction energy is about100kcal/mol. The function model is given priority to Middle model. The CO2gases dissolve in the gaps of guanidinium ionic liquid, which doesn’t obviously influence the structure of the ion pairs. There are35figures,37tables and252references.更多还原