Mafuné Fumitaka, Takenouchi Masato, Miyajima Ken, Kudoh Satoshi
Department of Basic Science, School of Arts and Sciences, The University of Tokyo , Komaba, Meguro, Tokyo 153-8902, Japan.
J Phys Chem A. 2016 Jan 28;120(3):356-63. doi: 10.1021/acs.jpca.5b09531. Epub 2016 Jan 14.
Gas-phase rhodium oxide clusters, RhnOm(+), were investigated by measuring the rate constants of oxidation and thermal desorption spectrometry. RhnOm(+) was suggested to be categorized into different states as m/n ≤ 1, 1 < m/n ≤ 1.5, and 1.5 < m/n in terms of energy and kinetics. For m/n ≤ 1, the O atoms readily adsorbed on the cluster with a large binding energy until RhO was formed. Under the O2-rich environment, oxidation proceeded until Rh2O3 was formed with a moderate binding energy. In addition, O2 molecules attached weakly to the cluster, and Rh2O3 formed RhnOm(+) (1.5 < m/n). The energetics and geometries of Rh6Om(+) (m = 6-12) were obtained using density functional theory calculations and were found to be consistent with the experimental results.
通过测量氧化速率常数和热脱附光谱，对气相氧化铑团簇RhnOm(+)进行了研究。从能量和动力学角度来看，RhnOm(+)被建议分为m/n ≤ 1、1 < m/n ≤ 1.5和1.5 < m/n三种不同状态。对于m/n ≤ 1，氧原子以较大的结合能容易地吸附在团簇上，直到形成RhO。在富氧环境下，氧化过程持续进行，直到形成具有中等结合能的Rh2O3。此外，O2分子与团簇的结合较弱，并且Rh2O3形成了RhnOm(+)（1.5 < m/n）。利用密度泛函理论计算得到了Rh6Om(+)（m = 6 - 12）的能量和几何结构，发现与实验结果一致。
