Lidiya A. Koroleva, Alexandra V. Koroleva
Comparative
analysis of the capabilities of spectral methods in studying internal rotation
of compounds of the benzoic series
Abstract
Abstract. In the review the comparison of
the methods used to study internal rotation (IR) in the ground (S0)
and excited (S1) electronic states for compounds of the benzoic
series C6H5COR, where R = H, F, CI. In (S0)
electronic state differences in the values of (0-v) transitions of torsional vibration for studied
compounds are revealed in the methods of analysis of the vibrational structure
of n-π* transition of high-resolution UV absorption spectra and
IR-Fourier-spectra. The reasons for such differences are established. In the
excited (S1) state for benzaldehyde a comparison was made between
the method of analyzing the vibrational structure of n-π*
transition of high-resolution UV absorption spectra and the method of analyzing
the excitation spectra of sensitized phosphorescence of this compound in a
cooled jet. It is concluded that the method of analyzing the vibrational
structure of n-π* transition of high-resolution UV absorption spectra of
vapors of the investigated compounds is more reliable and accurate when studying
(IR) in both electronic states.
Key words:ν frequency of torsional
vibration, v vibrational quantum number, ω wavenumber, Deslandres table (DT), the ground and
excited electronic states
Copyright (C) Chemistry Dept., Moscow State University, 2002
|
|