The Action of the Electric Field on Absorption Spectra of Solutions: Electrochromism Spectra, Their Properties, and Operations with Them

摘要

Theoretical foundations of molecular absorption spectroscopy of solutions in external electric fields are considered. The action of the field varies the energies of the ground and the excited states of a molecule participating in a vibronic transition, which induces specific deformations in the spectra, which are called the electrochromism spectra. The dichroism of solutions appearing in the field also belongs to them. One can determine from electrochromism the spectra parameters of molecules in the ground and excited electronic states, study slow thermal mobility in solutions and the direction of displacement of the electron density of reacting molecules, and determine their other properties, which are difficult to measure by usual methods. An interpretation of electrochromism based on clear-cut physical principles is proposed. Electrochromism is considered as a natural branch of absorption molecular spectroscopy.