Sunahori Fumie X, Smith Tony C, Clouthier Dennis J
Department of Chemistry and Biochemistry, Rose-Hulman Institute of Technology, 5500 Wabash Ave., Terre Haute, Indiana 47803, USA.
Ideal Vacuum Products, LLC, 5910 Midway Park Blvd. NE, Albuquerque, New Mexico 87109, USA.
J Chem Phys. 2022 Jul 28;157(4):044301. doi: 10.1063/5.0101060.
The AlCH free radical has been spectroscopically identified for the first time. This highly reactive species was produced in an electric discharge jet using trimethylaluminum vapor in high pressure argon as the precursor. The laser-induced fluorescence spectrum of the B̃A-X̃B band system in the 513-483 nm region was recorded, and the 0-0 bands of AlCH and AlCD were studied at high resolution. The fine structure splittings were found to be due primarily to the Fermi contact interaction in the excited state rather than the usual spin-rotation coupling. Rotational analysis gave the molecular constants of the combining states, and the geometries were obtained as rA1-C=1.9591A◦,rC-H=1.1061A◦,θ =110.41 and rA1-C=1.9431A◦,rC-H=1.0911A◦,θ =115.41. The bond lengths correspond to an aluminum-carbon single bond in both states.
首次通过光谱法鉴定出了AlCH自由基。这种高反应活性的物种是在以高压氩气中的三甲基铝蒸气为前驱体的放电射流中产生的。记录了513 - 483nm区域内B̃A - X̃B带系的激光诱导荧光光谱，并在高分辨率下研究了AlCH和AlCD的0 - 0带。发现精细结构分裂主要是由于激发态中的费米接触相互作用，而非通常的自旋 - 旋转耦合。转动分析给出了结合态的分子常数，得到的几何结构为rA1 - C = 1.9591A◦，rC - H = 1.1061A◦，θ = 110.41以及rA1 - C = 1.9431A◦，rC - H = 1.0911A◦，θ = 115.41。两种状态下的键长均对应于铝 - 碳单键。
