Photolysis of methyl nitrate (CH3ONO2) through the prism of ab initio simulations of transient-absorption pump-probe spectra

Juanjuan Zhang; Deping Hu; Jiawei Peng; Maxim F Gelin; Zhenggang Lan

doi:10.1063/5.0256037

Photolysis of methyl nitrate (CH3ONO2) through the prism of ab initio simulations of transient-absorption pump-probe spectra

J Chem Phys. 2025 Jun 14;162(22):224302. doi: 10.1063/5.0256037.

Authors

Juanjuan Zhang¹, Deping Hu², Jiawei Peng¹, Maxim F Gelin³, Zhenggang Lan¹

Affiliations

¹ SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety and MOE Key Laboratory of Environmental Theoretical Chemistry, School of Environment, South China Normal University, Guangzhou 510006, China.
² Center for Advanced Materials Research, Beijing Normal University, Zhuhai 519087, China.
³ School of Science, Hangzhou Dianzi University, Hangzhou 310018, China.

PMID: 40492560
DOI: 10.1063/5.0256037

Abstract

The photolysis of methyl nitrate (CH3ONO2) UV-excited to the optically bright state is scrutinized by on-the-fly trajectory surface hopping simulations of dynamic observables and transient-absorption pump-probe (TA-PP) spectra. It is found that two major dissociation channels, CH3O + NO2 and CH3O + NO + O, are characterized by the two branches of the stimulated emission signal, which are clearly seen in the total experimentally detectable TA-PP signal. Correlations between the photolysis channels and their TA-PP signatures are established. It is argued that TA-PP spectra may provide valuable information on the multi-channel photolysis mechanisms in similar compounds, and combining ab initio simulations of the dynamic and spectroscopic observables may enhance our understanding of the photodissociation mechanisms and pathways.