Gao Han-Wen, Hui Jie, Wang Lai-Sheng
Department of Chemistry, Brown University, Providence, RI 02912, USA.
Chem Commun (Camb). 2023 Oct 17;59(83):12431-12434. doi: 10.1039/d3cc04235a.
Metal-boron triple bonds are rare due to the electron deficiency of boron. This study uncovers a simple electron-precise metal boryne complex, [BiBH], which is produced within an ion trap through chemical reactions of the open-shell BiB anion with H. Photoelectron imaging is used to investigate the electronic structure and chemical bonding of the BiBH complex. The B atom in the linear closed-shell BiBH is found to undergo sp hybridization, forming a B-H single bond and a BiB triple bond. Photoelectron imaging reveals three detachment transitions from the BiBH (Σ) anion to the neutral BiBH, including the ground state (Π) and two excited states (Σ and Π). Strong vibronic coupling is observed between the Π and Σ states, evidenced by the appearance of bending vibrations and their unique photoelectron angular distributions. The BiBH complex not only stands as the simplest metal boryne complex, but also serves as an ideal molecular system to investigate both spin-orbit and vibronic couplings.
由于硼的电子缺乏，金属 - 硼三键很罕见。本研究发现了一种简单的电子精确金属硼炔配合物[BiBH]，它是通过开壳层BiB阴离子与H在离子阱中发生化学反应生成的。光电子成像用于研究BiBH配合物的电子结构和化学键。发现线性闭壳层BiBH中的B原子进行sp杂化，形成一个B - H单键和一个BiB三键。光电子成像揭示了从BiBH (Σ)阴离子到中性BiBH的三个离解跃迁，包括基态(Π)和两个激发态(Σ和Π)。在Π和Σ态之间观察到强烈振动电子耦合，弯曲振动的出现及其独特的光电子角分布证明了这一点。BiBH配合物不仅是最简单的金属硼炔配合物，也是研究自旋轨道和振动电子耦合的理想分子体系。
