Subject: Franck-Condon factors?

From: "Mark Hanning-Lee" <[email-masked]>
Date: Tue, 17 Oct 1995 09:56:01 -0700

Where could I find a program to calculate Franck-Condon factors for an
electronic spectrum? Any software with some of the following features would be
welcome.

The program would read the energy of the vibrationless transition (0-0). For
each vibrational mode, it would also read the vibrational frequencies and
reduced masses in the upper and lower electronic states, and the normal
coordinate displacement between them.

It would then use harmonic (or suitable anharmonic) oscillator functions to
calculate the transition functions for the 0-0, 1-0, 2-0, ... bands and weight
them by E**4 (for emission) or E (for absorption).

As a real bonus, it would also convolute this "stick" spectrum with a
Gaussian, Voigt, or Lorentzian profile of specified linewidth, and print a
simulated spectrum.

(Would non-linear parameter fitting be too much to ask for? The calculated
spectrum would be normalized by the area under the experimental spectrum.)

I looked at Jandel's PeakFit, which can fit data to a series of overlapping
peaks, but seemed unable to handle the complex Franck-Condon relationships
between peak intensities, e.g. 0-0: 1-0 = 1: exp(-x**2/2).

I also looked at the Level program by Robert LeRoy, [email-masked]. This
seemed most impressive but perhaps more than I needed.

LeRoy mentioned programs from the Zare group; are any of those available?

Any help would be most welcome ... Thanks, Mark

Dr. Mark A. Hanning-Lee    |  Tel:  (310) 336 2835
The Aerospace Corporation  |  FAX:  (310) 336 7680
PO Box 92957, M5-754       |
Los Angeles CA 90009-2957  |  Email: [email-masked]
USA