Subject: Two photon absorption cross section units

From: Jesús Orduna <[email-masked]>
Date: Wed, 24 Apr 2002 12:45:09 +0200

dear CCLers,

I am becoming interested in Two Photon Absortion (TPA) processes and the use of quantum chemical calculations to predict TPA cross sections.

> From a three level aproach, the TPA cross section is expresed as:

 (mu(0,1))^2 (mu(1,2))^2/(delta E)^2

So it should have the dimensions of  "dipole moment^4/Energy^2"

but the TPA cross section is usually expresed in "cm^4 s/molecule" units which at least at first sight have a completely different dimension.

Could somebody clarify the relationship between these ways to express the TPA cross sections?

How can I convert calculated croos sections in atomic units to cm^4 s/molecule?

Thanks

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Jesús Orduna
Instituto de Ciencia de Materiales de Aragon
Unidad de Nuevos Materiales Orgánicos
Facultad de Ciencias
CSIC-Universidad de Zaragoza
E-50009 Zaragoza (Spain)
Phone/FAX: +34 976 761194
e-mail: [email-masked]
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