From owner-chemistry@ccl.net Tue Jul 25 11:48:01 2006 From: "Abrash, Samuel sabrash*o*richmond.edu" To: CCL Subject: CCL:G: Scale factor Message-Id: <-32245-060725112656-5612-/nTmudLhDa9AlaIJWlFDdw+*+server.ccl.net> X-Original-From: "Abrash, Samuel" Content-class: urn:content-classes:message Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="us-ascii" Date: Tue, 25 Jul 2006 11:26:50 -0400 MIME-Version: 1.0 Sent to CCL by: "Abrash, Samuel" [sabrash===richmond.edu] NIST's Computational Chemistry Comparison and Benchmark Database (also known as CCCBDB and found at http://srdata.nist.gov/cccbdb/ has scaling factors for a large number of combinations of theory and basis set. Go to the webpage cited above, and click on Vibrations. Scaling factors are in section C. Sam Abrash -----Original Message----- > From: owner-chemistry]-[ccl.net [mailto:owner-chemistry]-[ccl.net] Sent: Tuesday, July 25, 2006 2:11 AM To: Abrash, Samuel Subject: CCL:G: Scale factor Sent to CCL by: "Tapan Gupta" [tapanjames(_)yahoo.com] Dear Sir, In the Book "Exploring Chemistry with Electronic structure methods by J. B Foresman and Frisch" under the chapter Frequency calculations, the Scale factor are given as follows Method Scale Factor Frequency ZPE/Thermal HF/3-21G 0.9085 0.9409 HF/6-31G(d) 0.8929 0.9135 MP2(Full)/6-31G(d) 0.9427 0.9646 MP2(FC)/6-31G(d) 0.9434 0.9676 SVWN/6-31G(d) 0.9833 1.0079 BLYP/6-31G(d) 0.9940 1.0119 BL3YP/6-31G(d) 0.9613 0.9804 Further it is written that "You should be aware that the optimal scaling factors vary by basis set" My Question is that what will be the scaling factor if I am using 6-31G(d,p) basis set for a Opt+Freq Calculation of a molecule of 14 atoms using MP2 level of theory ? (As scale factor for 6-31G(d,p) is not given in the table) Whether this scale factor has to multiplied manually to each frequency or it is automatically done by Gaussian ? Also, if there is any other book/books which are best for using Gaussian then plsss tell me. Sorry if the Question is too Basic Thanks in advance Sincerely, Tapanhttp://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp://www.ccl.net/chemistry/sub_unsub.shtmlhttp://www.ccl.net/spammers.txt