N路路路I Halogen Bonding Interactions: Influence of Lewis Bases on Their Strength and Characters

详细信息    查看全文

• 作者：Na Han ; Yanli Zeng ; Cuihong Sun ; Xiaoyan Li ; Zheng Sun ; Lingpeng Meng
• 刊名：Journal of Physical Chemistry A
• 出版年：2014
• 出版时间：August 28, 2014
• 年：2014
• 卷：118
• 期：34
• 页码：7058-7065
• 全文大小：340K
• ISSN：1520-5215

文摘

Halogen bonding (XB) as an emerging noncovalent interaction, due to its highly directional and devisable properties, has given rise to considerable interest for constructing supramolecular assemblies. In this work, the newly developed density functional M06-2X calculations and the quantum theory of 鈥渁toms in molecules鈥?(QTAIM) studies were carried out on a series of N路路路I halogen bonding to investigate the influence of Lewis bases (XB acceptors) on the XB. For the Lewis base C_6鈥?i>nH_6鈥?i>nN_n (n = 1, 2, 3), with the increasing number of nitrogen atom in the aromatic ring, the most negative electrostatic potentials (V_S,聽min) outside the nitrogen atom becomes less negative and the XB becomes weaker. The positive cooperativity exists in the Y^{鈥?/sup>鈥揅₆H₅N路路路C₆F₅I, Y鈥?/sup>鈥揅₄H₄N₂路路路C₆F₅I, and Y鈥?/sup>鈥揅₃H₃N₃路路路C₆F₅I (Y鈥?/sup> = Cl鈥?/sup>, Br鈥?/sup>, I鈥?/sup>) termolecular complexes: the H bond or anion鈭捪€ interactions have the ability to enhance the N路路路I halogen bond and vice versa. With the addition of halogen anions to the XB acceptor, the XB become more covalent, more electronic charge transfer from the XB acceptors to donors, the XB acceptors become more energetically stabilized and XB donors become more destabilized, and the atomic volume attraction of both the nitrogen and iodine atoms become more obvious. From the view of the Laplacian of electron density function, for the XB acceptor, the reactivity zone is the region of valence shell charge concentration (VSCC), where it is a (3, 鈭?) critical point (CP) and referred to as a lump, thus the XB interaction can be classified as a lump鈥揾ole interaction. The more negative V_S,min outside the nitrogen atom, the stronger the XB, resulting in the greater distance between the (3, 鈭?) CP and the nitrogen nucleus.}