Iodization Threshold in Size-Dependent Reactions of Lead Clusters Pbn+ with Iodomethane

Mengzhou Yang; Haiming Wu; Benben Huang; Zhixun Luo; Klavs Hansen

doi:10.1021/acs.jpca.0c01413

Iodization Threshold in Size-Dependent Reactions of Lead Clusters Pb_n⁺ with Iodomethane

J Phys Chem A. 2020 Mar 26;124(12):2505-2512. doi: 10.1021/acs.jpca.0c01413. Epub 2020 Mar 5.

Authors

Mengzhou Yang^{1

2}, Haiming Wu^{1

2}, Benben Huang^{1

2}, Zhixun Luo^{1

2}, Klavs Hansen^{3

4}

Affiliations

¹ Beijing National Laboratory for Molecular Sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
² University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
³ Joint Centre for Quantum Studies and Department of Physics, School of Science, Tianjin University, Tianjin, P. R. China.
⁴ Department of Physics, University of Gothenburg, 41296 Gothenburg, Sweden.

PMID: 32091897
DOI: 10.1021/acs.jpca.0c01413

Abstract

Utilizing a magnetron-sputtering (MagS) source in tandem with a multiple-ion laminar flow tube (MIFT) reactor and a customized triple quadrupole mass spectrometer (TQMS), we have prepared clean Pb_n⁺ (n = 1-13) clusters and measured their reactivity with iodomethane under high carrier gas pressures. Strong size dependences are found for the reactivity of these cationic Pb_n⁺ clusters with CH₃I. For the Pb_n⁺ with n ≤ 4, iodinated clusters Pb_nI⁺ were found to be the dominant products, in strong contrast to n > 4 where no such products were seen. Quantum chemical studies show that with an increasing number of Pb atoms, the Pb-Pb interatomic interactions become stronger compared with the Pb-I bonding in Pb_nI⁺ clusters. Furthermore, the reactions of Pb_1-4⁺ with CH₃I have fairly small transition state energy barriers, in contrast to those for Pb_n>4⁺ clusters which have magnitudes that will prevent reactions under the ambient conditions.