A line-shape function in terms of changes in both molecular structure and force constants: A Gaussian approximation
- 16 February 2006
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 124 (7), 074304
- https://doi.org/10.1063/1.2166630
Abstract
We propose a new expression of a line-shape function (LSF) including the effects of changes in both force constants and the molecular structure within the harmonic-oscillator approximation. This expression enables us to calculate the LSF using only the data on molecular structures, force constants, and electronic energies in the initial and final electronic states without solving the eigenvalue equation for the normal vibration of a molecule. To derive the LSF expression, we consider one-photon emission from a polyatomic molecule thermalized in an electronic excited state, and derive the intensity distribution function for one-photon emission using not Lax and Kubo and Toyozawa’s [J. Chem. Phys.20, 1752 (1952); Prog. Theor. Phys.13, 160 (1955)] generating function method but rather the density-matrix method. As a simple application, a Gaussian approximate LSF is applied to S O 2 . As a result, it is found that the effect of change in force constants between the initial and final electronic states cannot be ignored, nor can the effect of change in the molecular structure between these two states. The LSF expression obtained is applicable to studies of not only radiative transition but also of electron-transfer and energy-transfer processes where both changes in molecular structure and force constants between the initial and final electronic states cannot be disregarded.Keywords
This publication has 26 references indexed in Scilit:
- Semiclassical evaluation of nonadiabatic rates in condensed phasesThe Journal of Chemical Physics, 1993
- Temperature Dependence of the Excitation Transfer in Photosynthetic SystemsJournal of the Physics Society Japan, 1978
- Temperature dependent activation energy for electron transfer between biological moleculesThe Journal of Chemical Physics, 1976
- The effect of intramolecular quantum modes on free energy relationships for electron transfer reactionsThe Journal of Chemical Physics, 1975
- Thermal electron transfer reactions in polar solventsThe Journal of Physical Chemistry, 1974
- Multiphonon Processes in the Nonradiative Decay of Large MoleculesThe Journal of Chemical Physics, 1970
- Phonon Sidebands, Multiphonon Relaxation of Excited States, and Phonon-Assisted Energy Transfer between Ions in SolidsPhysical Review B, 1970
- The energy gap law for radiationless transitions in large moleculesMolecular Physics, 1970
- Application of the Method of Generating Function to Radiative and Non-Radiative Transitions of a Trapped Electron in a CrystalProgress of Theoretical Physics, 1955
- The Franck-Condon Principle and Its Application to CrystalsThe Journal of Chemical Physics, 1952