CALCULATION OF HUANG-RHYS PARAMETERS AND THEORETICAL ANALYSIS OF INTEGRATED INTENSITIES AND PROFILE OF d-d OPTICAL SPECTRA lN NON-CONDON APPROXIMATION

We develop in this paper the theory of multiphonon radiative transition so that someimportant physical quantities that describe effect s of lattice relaxation in electron transitions,for example, Huang--Rhys parameters, lattice relaxation energies and Stokes shifts, becomecomputable directly. The calculated results of the se physical quantities for alexandrite agreewith experimental data very well. Besides, we deduce expressions of intensity distributionand integrated intensity of a multiphonon sideband in non--Condon approximation. The cal-culated values of integrated intensities are obviously better than the intensity fitting resultsof previous work. From these calculated values we can also acquire a quantitative under-standing of the errors of Condon approximation.