CCL:G: High virial ratio

 Sent to CCL by: Toomas Tamm [tt-ccl2..yki.ttu.ee]
 On Fri, 2011-09-23 at 23:57 -0400, Sandhya Rai
 sandhyachemistry30*o*gmail.com wrote:
 > I am studying metal interactions with biomolecules. Some times I get
 > very high virial ratio like 4.09 etc. The frequency values are all
 > real and the output structures are also fine. Can any one suggest me
 > what might be going wrong. The metal I use is gold
 You do not say what method, basis set, or software you use, but assuming
 you use DFT with some common software such as Gaussian, you (or the
 software) probably have selected a pseudopotential (ECP) containing
 basis set for gold. If this is the case, the virial theorem indeed does
 not hold for your system.
 For an explanation, see, for example,
 http://www.ccl.net/cgi-bin/ccl/message-new?1997+01+30+016
 --
 Toomas Tamm                                 e-mail: tt-ccl2 (at) kky . ttu . ee
 Chair of Inorganic Chemistry                voice:  INT+372-620-2810
 Tallinn University of Technology            fax:    INT+372-620-2828
 Ehitajate tee 5, EE-19086 Tallinn, Estonia  http://www.kk.ttu.ee/toomas/