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Date: Wed, 22 Mar 2000 15:39:14 +0100
From: Andreas Goeller <goeller {*at*} pc04.chemie.uni-jena.de>
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Dear CCLers,

from semiempirical calculations I get transition energies (say, in
wavenumbers, lam) and oscillator strengths (osc), i.e. a line spectrum.
The osc are proportional to the surface below one extinction curve. I
can model this curve approximately by using a Gauss curve f(x), and by
summation over all curves (g(x)) I get something comparable to an
experimental spectrum. The function is

g(x)= sum_i(osc_i*(fx_i))
f(x)= 1/(sigma*sqrt(2*pi))*exp(-0.5*((x-x0)/sigma)**2)

Can anybody give me a hint about reasonable choices for sigma, the
standard deviation? The smaller sigma, the steeper the curve. 


Thanks a lot for the answers I hope to get 

-- 
                                Andreas Goeller

---------------------------------------------------------------
   Dr. Andreas Goeller       Institut fuer Physikalische Chemie
                               Friedrich-Schiller-Universitaet
                                       Lessingstr. 10
phone: +49(0)-3641-948352               D-07743 Jena
  fax: +49(0)-3641-948302 (secretary)     Germany
email: goeller: at :pc04.chemie.uni-jena.de
http://www.uni-jena.de/chemie/photo/goeller/goeller.html
---------------------------------------------------------------
   Dr. Andreas Goeller   ehemals Computer Chemie Centrum

email: goeller #at# organik.uni-erlangen.de
http://www.organik.uni-erlangen.de/clark/goeller/goeller.html
---------------------------------------------------------------