CCL: How to calculate the independent degrees of freedom of a molecule?
- From: Sten Nilsson Lill <stenil===chalmers.se>
- Subject: CCL: How to calculate the independent degrees of freedom
of a molecule?
- Date: Sun, 4 Dec 2011 17:10:24 +0100
Sent to CCL by: Sten Nilsson Lill [stenil,chalmers.se]
Hello Jun Zhang,
I hope this paper by Pople and colleagues is helpful:
J. A. Pople, Y. A. Sataty and E. A. Halevi, The Number of Independent Internal
Coordinates in Symmetrical Molecules, Israel J. Chem. 19, 290 (1980).
Hope it helps,
Sten
Ph.D. Sten Nilsson Lill
Dep. of Chemistry
University of Gothenburg
SE-412 96 Gothenburg, Sweden
e-mail: stenil,,chem.gu.se
Phone: +46-31 786 9103
Fax: +46-31-772 3840
________________________________________
> From: owner-chemistry+stenil==chem.gu.se,,ccl.net
[owner-chemistry+stenil==chem.gu.se,,ccl.net] On Behalf Of Jun Zhang coolrainbow
* yahoo.cn [owner-chemistry,,ccl.net]
Sent: Saturday, December 03, 2011 2:11 AM
To: Nilsson Lill, Sten
Subject: CCL: How to calculate the independent degrees of freedom of a molecule?
Hello everyone:
For a nonlinear N-atom molecule there are 3N-6 internal degrees of freedom, of
course. However, for a point group-constraint molecule, such as C2v H2O, there
are only 2 independent degrees of freedom. So, is there a systematic way to
determine the number and the contents of independent degrees of freedom of an
arbitarily symmetry-constraint molecule? I heard that some knowledge like Polya
theorem are requied, but I am not sure. It will be better if some reviews can be
reccommended.
Thank you in advance. Any suggestions will be appreciated.
Best regards!
----------------------------------------------------------------
Jun Zhang (coolrainbow^-^yahoo.cn)
Computational Chemistry Group
No.94, Weijinlu
Nankai University
Tianjin, China