Department of Quantum Chemistry, Nicolaus Copernicus University, Toruń, Poland.
J Phys Chem A. 2012 Mar 8;116(9):2322-32. doi: 10.1021/jp211606t. Epub 2012 Feb 22.
The nature of a hydride-halogen bond is investigated by means of high-level quantum mechanical calculations expended with symmetry-adapted perturbation theory (SAPT), quantum theory of atoms in molecules (QTAIM), and natural bond orbital (NBO) methods. As model hydride-halogen bonded systems complexes between either LiH or HBeH and either XCF(3) or XCCH (X = F, Cl, Br, I) are used. It is shown that the formation of a hydride-halogen bond leads to the elongation of the R(δ+)-H(δ-) hydride bond, which is accompanied by the blue shift of the ν(R-H) stretching vibration frequency and the increase of the IR intensity of this mode. All these effects, although untypical in the case of, e.g., hydrogen bonds, can be considered as rather typical for hydride-halogen bonded systems. The decomposition of the interaction energy based on the SAPT method clearly indicates the dominant role of the induction term, thus the inductive nature of a hydride-halogen bond in opposition to previous findings. NBO-based analysis indicates the charge transfer from the hydride molecule to the more remote parts of the halogen donor and that the elongation of the R-H bond is caused by the charge outflow from the σ(RH) bonding orbital.
通过使用高级量子力学计算方法（包括对称性自适应微扰理论（SAPT）、原子在分子中的量子理论（QTAIM）和自然键轨道（NBO）方法），研究了氢化物-卤素键的性质。选择 LiH 或 HBeH 与 XCF(3)或 XCCH（X = F、Cl、Br、I）形成的复合物作为模型氢化物-卤素键合体系。结果表明，形成氢化物-卤素键会导致 R(δ+)-H(δ-)氢键的伸长，同时伴随ν(R-H)伸缩振动频率的蓝移和该模式红外强度的增加。尽管在氢键等情况下不典型，但所有这些效应都可以被认为是氢化物-卤素键合体系的典型特征。基于 SAPT 方法对相互作用能的分解清楚地表明了诱导项的主导作用，从而与先前的研究结果相反，氢化物-卤素键具有诱导性质。基于 NBO 的分析表明，电荷从氢化物分子转移到卤素供体的更远部分，并且 R-H 键的伸长是由从σ(RH)成键轨道流出的电荷引起的。
