An intramolecular vibrationally excited intermolecular potential energy surface and predicted 2OH overtone spectroscopy of H2O-Kr

Xiao-Long Zhang; Shu-Bin Yang; Dan Hou; Hui Li

doi:10.1039/d3cp04126c

An intramolecular vibrationally excited intermolecular potential energy surface and predicted 2OH overtone spectroscopy of H₂O-Kr

Phys Chem Chem Phys. 2023 Nov 8;25(43):29940-29950. doi: 10.1039/d3cp04126c.

Authors

Xiao-Long Zhang¹, Shu-Bin Yang¹, Dan Hou², Hui Li³

Affiliations

¹ The Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Yantai University, Yantai 264005, P. R. China.
² Key Laboratory of Chemical Utilization of Plant Resources of Nanchang, College of Chemistry and Materials, Jiangxi Agricultural University, Nanchang 330045, P. R. China. houdan17@jxau.edu.cn.
³ Institute of Theoretical Chemistry, College of Chemistry, Jilin University, 2519 Jiefang Road, Changchun 130023, P. R. China. prof_huili@jlu.edu.cn.

PMID: 37902029
DOI: 10.1039/d3cp04126c

Abstract

A new five-dimensional potential energy surface (PES) for H₂O-Kr which explicitly includes the intramolecular 2OH overtone state of the H₂O monomer is presented. The intermolecular potential energies were evaluated using explicitly correlated coupled cluster theory [CCSD(T)-F12] with a large basis set. Four vibrationally averaged analytical intermolecular PESs for H₂O-Kr with H₂O molecules in its |00⁺〉, |02⁺〉, |02^-〉, and |11⁺〉 states are obtained by fitting to the multi-dimensional Morse/Long-Range potential function form. Each vibrationally averaged PES fitted to 578 points has root-mean-square (RMS) deviations smaller than 0.14 cm^-1 and requires only 58 parameters. The combined radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm were employed to calculate the rovibrational energy levels for |00⁺〉, |02⁺〉, |02^-〉, and |11⁺〉 states of the H₂O-Kr complexes. The calculated |02^-〉Π^f/e(1₀₁) ← |00⁺〉Σ^e(0₀₀) and |02⁺〉Π^f/e(1₁₀) ← |00⁺〉Σ^e(1₀₁) infrared transitions are in excellent agreement with the experimental values with RMS discrepancies being only 0.007 and 0.016 cm^-1, respectively. These analytical PESs can be used to provide reliable theoretical guidance for future infrared overtone spectroscopy of H₂O-Kr.