CCL:Linear dichroism.

["Jens Spanget-Larsen" <jsl { *at * } virgil.ruc.dk>]

Ali Rashid:
 > Hi, I was wandering if anyone knows of a way to simulate the
 > absorption spectra of a system. What i am interested in is, starting
 > from a model of a molecules or molecules packed in a certain way,
 > can i then calculate  things like the dichroic ratio and the linear
 > dichroism?  Thank you in advance. --
 Dear Ali,
 In principle, transition energies, oscillator strengths and
 transition moment directions of molecular optical transitions can be
 predicted by quantum chemical calculations (the presence of molecular
 symmetry elements may be of great help in this task). It is then
 possible to predict the dichroic ratio and the linear dichroism of an
 assembly of molecules "packed in a certain way", since the resulting
 absorption probability is proportional to the cosine-squared of the
 angle between the individual moment directions and the electric
 vector of the linearly polarized light. See the volume by Michl and
 Thulstrup:
 J. Michl, E. W. Thulstrup: "Spectroscopy with Polarized Light. Solute
 Alignment by Photoselection, in Liquid Crystals, Polymers, and
 Membranes", VCH Publishers 1986, 1995 (ISBN 1-56081-910-3).
 Yours, Jens >--<
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 JENS SPANGET-LARSEN         Office:     +45 4674 2710
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