From owner-chemistry@ccl.net Mon Jun 12 04:30:00 2017 From: "Mark Andrew Blitz m.blitz .. leeds.ac.uk" To: CCL Subject: CCL: MESMER 5.0 Message-Id: <-52836-170612042702-9516-JjDuXVW+bSbYQzvA7gkovg^^server.ccl.net> X-Original-From: "Mark Andrew Blitz" Date: Mon, 12 Jun 2017 04:27:00 -0400 Sent to CCL by: "Mark Andrew Blitz" [m.blitz[-]leeds.ac.uk] Dear Colleague, On behalf of the MESMER team, we are delighted to announce that MESMER 5.0 (Master Equation Solver for Multi Energy-well Reactions) is now available for download. MESMER is designed to analyze and simulate reactions in the gas phase that take place on a potential energy surface that is characterized by having one or more potential wells, and which are typically described by rate coefficients that depend on pressure (or concentration) as well as temperature. MESMER allows you to simulate systems over a wide range of pressures and temperatures, extract rate coefficients, analyze experimental data, fit model parameters and represent rate coefficients in formats that can be used directly in large scale simulations (e.g. Cantera or Chemkin). The Windows installer and Linux tar file are located at: http://sourceforge.net/projects/mesmer/ The source can also be viewed and downloaded from this site. There are also bug and feature request tracking facilities which we encourage you to use. The following new features have been implemented: MPI parallelization of MESMER. Extended fragmentation distribution. New class for reading in density of states. Implementation of the 1D Fourier grid vibrational state calculator. Implementation of the Zhu-Nakamura non-adiabatic microcanonical rate coefficient algorithm. Other changes: The reporting of errors from a fitting exercise has been altered, such that if explicit error estimates for each data point appear in the input file then a goodness of fit is calculated, otherwise errors in parameters are estimated on the basis of ^2 per degree of freedom of unity. A new molecular property, me:TSOpticalSymmetryNumber, has been added that allows the specification of the number of transition state optical isomers. If you have any comments or suggestions, please do not hesitate to let us know, either through the above site or by email (Mark Blitz(M.Blitz : leeds.ac.uk) and Struan Robertson(struanhrobertson : gmail.com) would be very happy to receive feedback). More information is available at the MESMER website: http://www.chem.leeds.ac.uk/mesmer.html Also some of the implementation details of MESMER are described in Journal of Physical Chemistry A, 95459560, 116 (2012). A web based graphical user interface for creating MESMER input files, develop by Dr. Xiaoqing You and colleagues of the University of Tsinghua, in collaboration with the MESMER team, is available for testing and can be found at the following address: http://www.cce.tsinghua.edu.cn:8000/ Dr. You and the MESMER team would welcome feedback on this interface. We would like to acknowledge useful discussion and feedback from Zachary Buras and Matthew Johnson of MIT and Charles McGill of NCSU. Regards, Mark Blitz and Struan Robertson Mark Blitz School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT. U.K. Tel 0113 343 6594 Email: M.Blitz : leeds.ac.uk From owner-chemistry@ccl.net Mon Jun 12 22:36:00 2017 From: "Joseph Leonard jleonard42]~[gmail.com" To: CCL Subject: CCL: Torsion profiles (forcefield or QM) Message-Id: <-52837-170612222834-23955-tUGsUc0aUSw9eHcYF7bTbA[]server.ccl.net> X-Original-From: Joseph Leonard Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="UTF-8" Date: Mon, 12 Jun 2017 22:28:02 -0400 MIME-Version: 1.0 Sent to CCL by: Joseph Leonard [jleonard42_._gmail.com] Folks, I would appreciate learning of any literature citations that discuss torsion profiles (constrained minimization used to carry out rotatable bond scan). I am familiar with rapid, rigid-rotor scans, but they can lead to arbitrarily large energy barriers as the rest of the molecule cannot relax. This seems like an older idea, but I do not recall reading about it over the years nor hearing about it at conferences. The increased availability of computer power means that calculations can be done with QM codes as well but the results and I assume the various arguments for/against these calculations are the same. Thanks in advance! Joe -- “The problem with today’s world is that everyone believes they have the right to express their opinion AND have others listen to it. The correct statement of individual rights is that everyone has the right to an opinion, but crucially, that opinion can be roundly ignored and even made fun of, particularly if it is demonstrably nonsense!” — Brian Cox