From chemistry-request@server.ccl.net Thu Aug 24 17:06:25 2000 Received: from sirocco.cc.mcgill.ca (sirocco.CC.McGill.CA [132.206.27.12]) by server.ccl.net (8.8.7/8.8.7) with ESMTP id RAA21159 for ; Thu, 24 Aug 2000 17:06:25 -0400 Received: from ariyatwo (ariyatwo.Chem.McGill.CA [132.206.175.94]) by sirocco.cc.mcgill.ca (8.9.1/8.9.1) with SMTP id RAA23302 for ; Thu, 24 Aug 2000 17:06:25 -0400 (EDT) Message-Id: <200008242106.RAA23302@sirocco.cc.mcgill.ca> From: "Balakrishnan Viswanathan" Organization: Chemistry Dept., McGill University To: CHEMISTRY@ccl.net Date: Thu, 24 Aug 2000 17:06:24 -0400 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Subject: Hg and Zn Reply-to: viswana@chemistry.mcgill.ca X-Confirm-Reading-To: viswana@chemistry.mcgill.ca X-pmrqc: 1 Priority: normal X-mailer: Pegasus Mail for Win32 (v3.01d) Greetings CCLers, I noticed from a recent publication (Cundari, T.R. and Moody,E.W, Theochem 425 (1998) 43-50) on the calculation of formation enthalpies of 52 diatomic oxides, that the relative deviation from experiment was most pronounced for ZnO and HgO, in both cases, being larger than 100 %. In fact, the calculated enthalpies of formation had signs opposite to that obtained experimentally. It was also seen that all of the other oxides agreed to within 50 % relative to the experimental heat of formation. The calculations were carried out using MCSCF wavefunctions and ROHF method. Perhaps someone could please explain why ZnO and HgO behave in this anomalous manner and speculate whether the same is expected from the analogous CdO. I will summarise all responses which I receive. Thanks. Balakrishnan Balakrishnan Viswanathan viswana@chemistry.mcgill.ca Lab: (514) 398-6920 Fax: (514) 398-2382