Hou Jianhua, Duan Qian, Qin Jieming, Shen Xiande, Zhao Jianxun, Liang Qingcheng, Jiang Dayong, Gao Shang
School of Materials Science and Engineering, Changchun University of Science and Technology, Changchun 130022, People's Republic of China.
Phys Chem Chem Phys. 2015 Apr 21;17(15):9644-50. doi: 10.1039/c5cp00254k.
Planar wheel-type D6h M©B6H6(-/0/+) (M = Mn, Fe and Co for anion, neutral and cation, respectively.) clusters with a planar hexacoordinate transition-metal at the center of the boron ring were designed and investigated by density functional theory. These planar clusters are chemically stable as a result of their large binding energy, vertical ionization potential, and vertical electron affinity. The detailed natural population and molecular orbital analyses suggest that not only does the M atom donate electrons to the boron ring for participation in the π-delocalized bonding, but also the boron ring donates electrons back to the M atom for the formation of the σ-delocalized bonding, which leads to a strong aromaticity and unconventional charge distribution, i.e., the M atom is negatively charged, while the boron ring is positively charged. This study may open a new area in coordination chemistry for planar hexacoordinate transition metals and we expect further experimental exploration of their synthesis and potential applications.
设计并通过密度泛函理论研究了平面轮式D6h M©B6H6（- / 0 / +）（M分别对应阴离子、中性和阳离子时为Mn、Fe和Co）簇，其硼环中心有一个平面六配位过渡金属。由于具有较大的结合能、垂直电离势和垂直电子亲和能，这些平面簇在化学上是稳定的。详细的自然布居和分子轨道分析表明，不仅M原子向硼环提供电子以参与π离域键合，而且硼环也向M原子提供电子以形成σ离域键合，这导致了强烈的芳香性和非常规的电荷分布，即M原子带负电，而硼环带正电。这项研究可能为平面六配位过渡金属的配位化学开辟一个新领域，我们期待对其合成和潜在应用进行进一步的实验探索。
