Li Sheng, Fu Xiaoxi, Chen Xiaolin, Lu Yuzhu, Ning Chuangang
Department of Physics, State Key Laboratory of Low Dimensional Quantum Physics, Tsinghua University, Beijing 100084, China.
J Chem Phys. 2022 Jul 28;157(4):044302. doi: 10.1063/5.0101903.
The tantalum anion has the most complicated photoelectron spectrum among all atomic anions of transition elements, which was the main obstacle to accurately measure its electron affinity via the generic method. The latest experimental value of the electron affinity of Ta was 0.323(12) eV, reported by Feigerle et al. [J. Chem. Phys. 74, 1580 (1981)]. In the present work, we report the high-resolution photoelectron spectroscopy of Ta via the slow-electron velocity-map imaging method combined with a cryogenic ion trap. The electron affinity of Ta was measured to be 2652.38(17) cm or 0.328 859(23) eV. Three excited states D, P, and D of Ta were observed, and their energy levels were determined to be 1169.64(17) cm for D, 1735.9(10) cm for P, and 2320.1(20) cm for D above the ground state D, respectively.
钽阴离子在所有过渡元素的原子阴离子中具有最复杂的光电子能谱，这是通过通用方法准确测量其电子亲和能的主要障碍。钽电子亲和能的最新实验值为0.323(12) eV，由费格勒等人报道[《化学物理杂志》74, 1580 (1981)]。在本工作中，我们报道了通过慢电子速度成像方法结合低温离子阱对钽进行的高分辨率光电子能谱研究。测得钽的电子亲和能为2652.38(17) cm或0.328 859(23) eV。观察到钽的三个激发态D、P和D，它们的能级相对于基态D分别为1169.64(17) cm、1735.9(10) cm和2320.1(20) cm。
