From owner-chemistry@ccl.net Fri Oct 29 08:46:00 2010 From: "wuxiao xiaowu759]~[hotmail.com" To: CCL Subject: CCL: oplsaa force field parameter of EPON862 containing -CH2- group linked to two phenyl Message-Id: <-43033-101029050344-14555-/XuwdWNfG2AtSUTC08/R8A[*]server.ccl.net> X-Original-From: wuxiao Content-Type: multipart/alternative; boundary="_23880ecb-b330-467e-8084-b4315de4033f_" Date: Fri, 29 Oct 2010 17:03:32 +0800 MIME-Version: 1.0 Sent to CCL by: wuxiao [xiaowu759 a hotmail.com] --_23880ecb-b330-467e-8084-b4315de4033f_ Content-Type: text/plain; charset="gb2312" Content-Transfer-Encoding: 8bit Dear CCLers, I want to simulate an epoxy resin, EPON862, using oplsaa force field in gromacs. In the molecules, there are -CH2- group which are linked to two phenyl. In the parameter file of oplsaa force field, I can not find the suitable atom type for the C atoms. Instead, I had tried the opls_149 (CH3, toluene) or opls_148(CH2, ethyl benzene), which led to fatal errors. One of possible solution to my problem can be creating new atom type for -CH2-, but it is very hard work to optimize the parameters. So, have you happened to simulate/find such a similar molecule(there are -CH2- group which are linked to two phenyl) in the format of oplsaa force field? If yes, please kindly give me the references. Thanks a lot! yours sincerely, Chaofu Wu, Dr. --_23880ecb-b330-467e-8084-b4315de4033f_ Content-Type: text/html; charset="gb2312" Content-Transfer-Encoding: 8bit
Dear CCLers,
  I want to simulate an epoxy resin, EPON862, using oplsaa force field in gromacs. In the molecules, there are -CH2- group which are linked to two phenyl. In the parameter file of oplsaa force field, I can not find the suitable atom type for the C atoms. Instead, I had tried the opls_149 (CH3, toluene) or opls_148(CH2, ethyl benzene), which led to fatal errors. One of possible solution to my problem can be creating new atom type for -CH2-, but it is very hard work to optimize the parameters. So, have you happened to simulate/find such a similar molecule(there are -CH2- group which are linked to two phenyl) in the format of oplsaa force field? If yes, please kindly give me the references. Thanks a lot! 
yours sincerely,
Chaofu Wu, Dr.
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