Electrical anharmonicity in hydrogen bonded systems: complete interpretation of the IR spectra of the Cl-H[combining right harpoon above] stretching band in the gaseous (CH3)2OHCl complex.
Following the previous developments to simulate the fully infrared spectra of weak hydrogen bond systems within the linear response theory, an extension of the adiabatic model is presented here. A general formulation including the electrical anharmonicities in the calculation of the damped autocorrelation function of weak H-bonds is adopted to facilitate the support of the additional properties, and thus the IR spectra of the Cl-H[combining right harpoon above] stretching band in the gaseous (CH3)2OHCl complex. We have explored the origins of the broadening of the Cl-H[combining right harpoon above] stretching band. We found that the main features of the lineshape are attributed to electrical anharmonicity as a consequence of the large mixed second derivatives of the dipole moment with respect to the Cl-H[combining right harpoon above] bond and of the intermonomer elongations . In addition to providing more accurate theoretical band shapes, inclusion of the electrical anharmonicity in the present model paves the way for a more complete interpretation by generating three new Franck-Condon superposed distributions.
Physics Department, Faculty of Science, University of Ha'il, Kingdom of Saudi Arabia. na.rekik@uoh.edu.sa and Laboratoire de Physique Quantique, Faculté des Sciences de Monastir, 5019 Monastir, Tunisia. rekik.najeh@fsm.rnu.tn.
Najeh
http://orcid.org/0000-0001-5347-1090
N
Rekik
Physics Department, Faculty of Science, University of Ha'il, Kingdom of Saudi Arabia. na.rekik@uoh.edu.sa.
Jamal
J
Suleiman
LAMPS, Université de Perpignan Via Domitia, 52, Avenue Paul Alduy, 66860 Perpignan cedex, France.
Paul
P
Blaise
Laboratory of Molecular Spectroscopy, Faculty of Chemistry, Jagiellonian University, Ingardena, 3, 30-060 Kraków, Poland.
Marek J
MJ
Wojcik
Institute of Chemistry, University of Silesia, 9 Szkolna Street, Pl-40-006 Katowice, Poland.
Henryk T
HT
Flakus
RIKEN Advanced Institute for Computational Science, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047, Japan.
Takahito
T
Nakajima