CCL:G: Confusing issue of Raman intensity Vs Static polarizability
- From: zborowsk#chemia.uj.edu.pl
- Subject: CCL:G: Confusing issue of Raman intensity Vs Static
- Date: Thu, 27 Nov 2008 15:13:33 +0100 (CET)
Sent to CCL by: zborowsk---chemia.uj.edu.pl
> Sent to CCL by: "Mi Yang" [miyang3790~~gmail.com]
> Dear Kzys!!
> Yes I am a gaussian03 Rev user but Your comments a bit confusing for me as
> in G03 manual it is clearly mentioned that by using Freq=Raman you can
> "Compute Raman intensities in addition to IR intensities" so I am
> understanding ur point of view.
Yes, it is true. It is true that in the Gaussian manual is clearly
mentioned that the program calculates Raman Intensities. But this
statement is not true, Gaussian does not serve Raman Intensities directly.
This is the reason of many mistakes. I do not know why Gaussian team does
not correct its manual.
I think that Vasile Chis clear some things in His letter. I can only add
that relationship that can be used for converting calculated Raman
activities to Raman intensities can be found also in
Michalska, Wysokinski, Chemical Physics Letters 403 (2005) 211?217
I think that the authors of this publication can send anyone free software
for calculation of Raman Intensities from Gaussian output
> There are some good quality of publications where they show computed raman
> intensities with gaussian e.g.
> J. AM. CHEM. SOC. 2005, 127, 10977-10981.pdf
> So I have stoped my work and first want to confirm it.
> Secondly, my calculated Freq value of Raman spectrum is in good agreement
> to the experimental value for specific mode of vibrations after scaling. I
> am not comparing directlt intensity with intensity.My purpose is to show
> increase of intensity or activity upon intercalation of metal atom.What do
> you think in this regard?
> I need your comments in detail especially in view of above references
In this case maybe you do not have to transform Raman Activities from
Gaussian into Raman Intensities. Of course bigger Raman Activity denote
stronger Raman Intensity for a particular band. The problem occur if you
want to reproduce the shape of whole raman spectrum for a molecule. On the
other hand calculation of Raman Intensities from Raman Activities is not