强激光场中第 10 族过渡金属氧化物小团簇的电离和库仑爆炸。

Ionization and Coulomb explosion of small group 10 transition metal oxide clusters in strong light fields.

机构信息

Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.

出版信息

J Chem Phys. 2012 Aug 28;137(8):084307. doi: 10.1063/1.4748139.

Abstract

The ionization properties of small group 10 metal oxide clusters are explored using ultrafast pulses centered at 624 nm. Maximum atomic charge states resulting from Coulomb explosion were observed to be Ni(3+), Pd(3+), Pt(5+), and O(2+) species with similar ionization potentials ~30-35 eV. Ion signal as a function of laser intensity of each charge state of Ni, Pd, Pt, and O resulting from Coulomb explosion was mapped and compared to that predicted from semi-classical tunneling theory using sequential ionization potentials to quantify observed enhancements in ionization. The saturation intensity (I(sat)) of each charge state is measured and compared to previous studies on group 5 transition metal oxides. The atomic charge states of nickel showed a large enhancement in ionization compared to palladium and platinum, reflective of the differing bonding properties of each metal with oxygen. Results indicate that nickel oxide clusters undergo a greater extent of ionization enhancement as a result of multiple ionization mechanisms. The ionization enhancement behavior of each metal oxide species is explored herein.

摘要

使用中心波长为 624nm 的超快脉冲探索了小群组 10 金属氧化物团簇的电离特性。观察到最大的原子电荷态是 Ni(3+)、Pd(3+)、Pt(5+)和 O(2+)，其电离势约为 30-35eV。通过比较库仑爆炸产生的 Ni、Pd、Pt 和 O 的每种电荷态的激光强度与离子信号，以及使用顺序电离势的半经典隧道理论来预测的信号，量化了观察到的电离增强。测量了每种电荷态的饱和强度 (I(sat))，并与之前对第 5 族过渡金属氧化物的研究进行了比较。镍的原子电荷态与钯和铂相比表现出较大的电离增强，反映了每种金属与氧的不同键合特性。结果表明，镍氧化物团簇由于多种电离机制而经历了更大程度的电离增强。本文探索了每种金属氧化物物种的电离增强行为。