【作者】 韩娜；

【导师】 曾艳丽； 郑世钧；

【作者基本信息】 河北师范大学 ， 物理化学， 2014， 硕士

【摘要】 分子间相互作用作为一种普遍存在的分子间作用形式，广泛应用于晶体工程、分子识别、材料化学等新兴领域。分子间相互作用不仅在化学领域得到了广泛的研究，同时在生命科学领域也得到了广泛的关注，成为科研工作者重点研究的课题之一。本文以几种典型的分子间相互作用卤键、氢键、阴离子π作用为研究对象，采用量子化学的微扰理论、密度泛函理论和“分子中的原子”量子理论对分子间相互作用进行了探究，分析弱键的成键、强度等定量指标，归纳增强分子间相互作用的影响因素。论文主要包括以下几方面的工作：1采用二阶微扰理论(MP2)、“分子中原子”量子理论和非共价相互作用指标(NCI)对复合物YC6F4X···C2H8N2(X=Cl, Br, I; Y=F, CN, NO2, LiNC+, NaNC+)中的X···N型卤键进行了研究。卤键供体中取代基的吸电子能力增强对卤原子的σ-hole处的大小和静电势局部极大值VS,max有正贡献，能够增强卤键。此外，在卤键供体中加入金属离子形成[MNCC6F4X]+，也能够增大σ-hole和VS,max使得电荷从卤键供体处转移，对卤键有增强作用。卤键供体卤原子的σ-hole处的VS,max值与卤键的相互作用能和结合距离存在很好的线性关系，说明在卤键中静电相互作用扮演着重要的角色。2在M06-2X方法下对Y-C6-nH6-nNn···C6F5I (n=1,2,3; Y=Cl, Br, I)复合物中N···I型卤键中XB受体对卤键强度的影响进行了研究，研究表明：卤键受体C6-nH6-nNn(n=1,2,3)分子，随着含氮六元杂环中氮原子个数的减少，形成的卤键相互作用增强。卤素阴离子Y-(Y-=Cl-, Br-, I-)的加入使得成键氮原子附近富集更多的电子，增强卤键的稳定性。Y-C6-nH6-nNn···C6F5I (n=1,2,3; Y=Cl, Br, I)复合物中的卤键是典型的闭壳层非共价相互作用，随着卤键受体中卤素阴离子的加入，形成的卤键共价性更明显，更多的电子电荷从卤键受体转移到卤键供体，使得卤键受体变得更稳定而卤键供体变得更不稳定。从电子密度拉普拉斯函数的观点可将卤键作用归类于“lump-hole”型相互作用。3在M06-2X/aug-cc-pVDZ下，对杂环杯芳烃tetraoxacalix[2]arene[2]triazine分子与四种具有代表性几何结构的阴离子(SCN、NO3、BF4和PF6)形成的复合物中的相互作用进行研究。杂环杯芳烃正电荷区域集中在分子的中心区域，阴离子与tetraoxacalix[2]arene[2]triazine分子的正电势区域相互吸引形成复合物。四种二聚体中存在氢键和anion π作用两种作用方式。四种二聚体中氢键键鞍点处的电子密度要明显强于阴离子π作用键鞍点处的电子密度，这说明杂环杯芳烃与阴离子形成的复合物中主要以氢键作用为主。根据QTAIM分析，四种二聚体间的相互作用都属于闭壳层非共价相互作用。本论文的创新点：1以晶体工程中具有广泛应用的卤键供体C6F5I及其衍生物为研究对象，研究分子表面静电势与卤键强度间的关系。首次将电子密度拓扑分析，电子密度拉普拉斯拓扑分析结合使用分析取代基的吸电子能力和金属离子的加入对卤键结合能力的影响。在此基础上通过NCI分析对卤键键鞍点附近的特征信息进行直观反映，并可视化卤键体系的相互作用类型和强度。2首次讨论了卤键受体对卤键强度的影响。以Y-C6-nH6-nNn···C6F5I (n=1,2,3; Y=Cl, Br, I)复合物中N···I型卤键为研究对象。通过电子密度拉普拉斯拓扑分析，对卤键受体局部电子浓集区进行深入分析。3首次探究了杂环杯芳烃tetraoxacalix[2]arene[2]triazine与阴离子间的弱相互作用。利用QTAIM分析，四种二聚体间的相互作用都属于闭壳层非共价相互作用并且氢键作用要强于阴离子π作用。更多还原

【Abstract】 The intermolecular interaction is a general interaction which was widely used in thecrystal engineering, molecular recognition, materials chemistry and so on. Intermolecularinteraction has been widely studied not only in the chemical area, but also the biological.In this work, several typical intermolecular interactions, such as halogen bond, hydrogenbond, and anion π interactions, were used as the object of study. The perturbation theory,density function theory and the quantum theory of “Atoms in Molecules” were carried out onthe intermolecular interactions. We summarized the influence factors of the intermolecularinteractions. There are mainly contained three sections:1. The second-order M ller Plesset perturbation theory (MP2) calculations, andquantum theory of “atoms in molecules”(QTAIM) and non-covalent interaction (NCI)studies were carried out on a series of X···N halogen bonds in the YC6F4X···C2H8N2(X=Cl,Br, I; Y=F, CN, NO2, LiNC+, NaNC+) complexes. The electron-withdrawing substituentsproduce an enhancement effect on the size of the σ-hole and the maximum positiveelectrostatic potentials (VS,max), which further strengthens the halogen bonding. The metallicion M+(M+=Li+, Na+) has the ability to enhance the size of both the σ-hole and VS,maxvaluewith the formation of [MNCC6F4X]+, resulting in more electronic charge transfer away fromthe halogen atom X and an increase in the strength of the halogen bond. It is found that thevalues of VS,maxat the σ-holes are linear in relation to the halogen-bonded interaction energiesand the halogen bonding interaction distance, indicating that the electrostatic interaction playsa key role in the halogen bonding interactions.2. The influence of halogen bond acceptors on a series of N···I halogen bonding in theY-C6-nH6-nNn···C6F5I (n=1,2,3; Y=Cl, Br, I) complexes were studied under the densityfunctional M06-2X level. For the halogen bond acceptors C6-nH6-nNn(n=1,2,3), with thedecreasing number of nitrogen atom in the aromatic ring, the most negative electrostaticpotentials (VS,min) outside the nitrogen atom becomes more negative and the halogen-bondedinteraction energies become greater. With the addition of halogen anions to the halogen bondacceptor, the XB become more covalent, more electronic charge transfer from the XBacceptors to donors, the XB acceptors become more energetic stabilization and XB donorsbecome more destabilization. The XB interaction in the Y-C6-nH6-nNn···C6F5I (n=1,2,3; Y=Cl, Br, I) complexes display the characteristics of “closed-shell” noncovalent interactions.From the view of the Laplacian of electron density function, the halogen bonding interactioncan be classified as lump-hole interaction. 3. The intermolecular interactions in the complexes of tetraoxacalix[2]arene[2]triazinewith the four typical polyatomic anions(SCN, NO3, BF4,and PF6) were studied at theM06-2X/aug-cc-pVDZ level. The region of the positive electrostatic potentials is focused onthe central region of tetraoxacalix[2]arene[2]triazine. The anions points to the positiveelectrostatic potential region of tetraoxacalix[2]arene[2]triazine formation of complexes. Theintermolecular interaction in the complexes has hydrogen bonding and anion π interactions.For the complexes, the electron density (ρb) at the BCP of hydrogen bonding are greater thanthe ρbat the BCP of anion π interactions, indicating that the hydrogen-bond interactions arestronger anion π interactions in the complexes. The interactions in complexes display thecharacteristics of “closed-shell” noncovalent interactions.The innovation in this thesis:1. The XB donor of substituted haloperfluoroarenes C6F4XY (X=Cl, Br, I; Y=F, CN,NO2) as bond donors, which was widely used in crystal engineering. We studied herelationship between the molecular electrostatic potentials and the strength of halogen-bondinteraction in the complexes. We sum analysis of the topological parameters of electrondensity and the topological parameters of the Lacplacian of electron density, indicating thatthe electron-withdrawing substituents and the metallic ion have the ability to enhance thehalogen-bond interaction. Visualize of the information of halogen-bond at BCP as regions ofreal space and distinguish of the types of interactions.2. Assessment of the influence of XB acceptors on the halogen-bond interactions isstudied firstly. The topological parameters of the Lacplacian of electron density was used tostudy the region of valence shell charge concentration in the Y-C6-nH6-nNn···C6F5I (n=1,2,3;Y=Cl, Br, I) complexes.3. The interaction in the complexes of tetraoxacalix[2]arene[2]triazine with the anionswere theoretical studies. The QTAIM studies have shown that these interaction of complexeswere the “closed-shell” noncovalent interactions and the hydrogen-bond interactions arestronger anion π interactions in the complexes.更多还原