Tan Zhao, Li An Yong
School of Chemistry and Chemical Engineering, Southwest University, Chongqing, 400715, People's Republic of China.
J Mol Model. 2018 Mar 9;24(4):90. doi: 10.1007/s00894-018-3605-z.
A novel type of trivalent BNg five-membered cational species BNg(Ng = HeRn, n = 15) has been found and investigated theoretically using the B3LYP and MP2 methods with the def2-QZVPPD and def2-TZVPPD basis sets. The geometry, harmonic vibrational frequencies, bond energies, charge distribution, bond nature, aromaticity, and energy decomposition analysis of these structures were reported. The calculated B-Ng bond energy is quite large (the averaged bond energy is in the range of 209.2585.76 kJ mol) for heavy rare gases and increases with the Ng atomic number. The analyses of the molecular wavefunction show that in the BNg compounds of heavy Ng atoms ArRn, the B-Ng bonds are of typical covalent character. Nuclear independent chemical shifts display that both B and BNg(n=1~5) have obvious aromaticity. Energy decomposition analysis shows that these BNg compounds are mainly stabilized by the σ-donation from the Ng valence p orbital to the B LUMO. These findings offer valuable clues toward the design and synthesis of new stable Ng-containing compounds.
一种新型的三价硼稀有气体五元阳离子物种BNg（Ng = HeRn，n = 15）已被发现，并使用B3LYP和MP2方法以及def2-QZVPPD和def2-TZVPPD基组进行了理论研究。报道了这些结构的几何形状、谐波振动频率、键能、电荷分布、键性质、芳香性和能量分解分析。对于重稀有气体，计算得到的B-Ng键能相当大（平均键能在209.2585.76 kJ mol范围内），并且随着Ng原子序数的增加而增加。分子波函数分析表明，在重Ng原子ArRn的BNg化合物中，B-Ng键具有典型的共价性质。核独立化学位移表明B和BNg（n = 1~5）都具有明显的芳香性。能量分解分析表明，这些BNg化合物主要通过从Ng价p轨道到B最低未占分子轨道的σ-给予作用而稳定。这些发现为新型稳定含Ng化合物的设计和合成提供了有价值的线索。
