From owner-chemistry@ccl.net Tue Aug 16 08:41:10 2005 From: "CCL" To: CCL Subject: CCL: W:Convergence problems in Oniom Message-Id: <-28969-050816083900-3020-jTKKlThOvCLwkE03HCXsVw{=}server.ccl.net> X-Original-From: "Walkimar Carneiro" Sent to CCL by: "Walkimar Carneiro" Dear friends, Im trying to run an optimization of a medium sized molecule using ONIOM (G03W) with three layers, b3lyp/6-31g(d), HF/3-21g and AM1 (or PM3). The ab initio SCF converges without any problem, the semi-empirical calculation, however, doesnt converge, mainly after some optimization cycles. I already tryed a lot of options recommended in gaussian manual to improve SCF convergence. Unfortunately, none of them worked. Does anybody can help me? With my best regards Walkimar Carneiro From owner-chemistry@ccl.net Tue Aug 16 09:13:40 2005 From: "CCL" To: CCL Subject: CCL: Announcement of ORCA Message-Id: <-28970-050816085148-6895-jTKKlThOvCLwkE03HCXsVw!=!server.ccl.net> X-Original-From: Frank Neese Content-Type: text/plain; charset="us-ascii"; format=flowed Mime-Version: 1.0 Sent to CCL by: Frank Neese Dear CCL'ers, hereby we announce the first public release of the ORCA electronic structure program which is available free of charge for academic users. ORCA is an efficient general purpose quantum chemistry program with extensive capabilities in the fields of Hartree-Fock theory, density functional theory, correlated ab initio methods and also semiempirical methods. The emphasis of the program is on transition metals and spectroscopy but it is expected to be useful in other areas as well. The program is essentially fully parallelized and available for a number of platforms including Windows, Linux and amd64 bit linux. The program comes with an extensive manual and is considered to be very user friendly. ORCA interfaces to a number of other major codes for specific purposes and produces output which is easily vizualized by a variety of graphics programs including molekel, gOpenMol and Chem3D. A full documentation together with instructions for downloading the executables can be found on our website. http://ewww.mpi-muelheim.mpg.de/bac/index_en.php simply go to the "download area" and follow the instructions how to download the code. You will have to agree to the license conditions. You will then receive a password via e-mail which lets you login into the download area where you will find the various manuals and executables. We have also installed a mailing list. To subscribe send an e-mail to: majordomo!=!mpi-muelheim.mpg.de subject (leave empty) message text: subscribe orca!=!mpi-muelheim.mpg.de to unscubscribe yourself do the same by replacing 'subscribe' by 'unsubscribe' To post a message to the mailing list send an e-mail to orca!=!mpi-muelheim.mpg.de ORCA has been developed over the past few years mainly by myself. More recently, a number of important contributions have been made by several members of my research group, namely Frank Wennmohs, Dmitry Ganyushin, Ute Becker and Taras Petrenko. We are most grateful to several collegues who have provided help and support. Higher-order Douglas-Kroll-Hess routines have been developed and kindly provided by Markus Reiher and Alexander Wolf (now university of Jena, germany), the redundant internal coordinate generation is based on code from Alain St-Amant and was communicated to me via John McKelvy, the COSMO model has been implemented into ORCA in a collaborative effort with COSMOlogic (Leverkusen, germany) - thanks to Andreas Klamt and Michael Diedenhofen. Many others have helped in various ways to bring the project to the point where it stands today and i am sincerely grateful to everybody who has contributed and has given us useful feedback. Since the number of users has been constantly growing and we received a significant amount of positive feedback and also since distributing the program became a significant commitment on our behalf, we have decided that it is time to release the program to the general public in the hope that it will turn out to be useful for your research. Since this is strictly academic code you have to expect to find a bug here and there - we are doing our best to produce a program which is as efficient, intuitive and bug free as possible but please understand that we do not have the resources available to provide a full featured support and cannot provide warranty of any kind. We will regularly inform the users of updates and new developments via the mailing list. Of course we appreciate your feedback, suggestions and criticism which are essential to make ORCA a better program! please enjoy the program! best regards, Frank Neese