On 2/5/20 12:54 PM, mbhendle wrote:
Hello all, I am trying to simulate polymers in tip4p-ice and for that I need to set two different "defaults" parameters for polymer chain and TIP4P-ICE in topology file. The "moleculetype" for Polymer chain and water is also different: [ defaults] ; nbfunc comb-rule gen-pairs fudgeLJ fudgeQQ (for polymer) 1 3 yes 0.5 0.5 [ defaults] ; nbfunc comb-rule gen-pairs fudgeLJ fudgeQQ (for TIP4P-ICE) 1 2 no 1 1 [moleculetype] ;Name nrexcl Other 3 ;(Polymer) SOL 1 ;(TIP4P-ICE) For this purpose, I have created two different ".itp" files for polymer chain and TIP4P-ICE. But while running "gmx grompp" gromacs is showing "Invalid order for directive moleculetype". I also tried putting two defaults parameters into ".top" file itself. But it also showed error. Please suggest how to do it.
You can't have two [defaults] directives. The gen-pairs, fudgeLJ, and fudgeQQ values only affect 1-4 interactions, which are not applicable to water, so I don't understand why they're relevant. You certainly can't mix different combination rules in a system, but you could specify different nonbonded parameters via [nonbond_params] rather than trying to specify different combination rules.
-Justin -- ================================================== Justin A. Lemkul, Ph.D. Assistant Professor Office: 301 Fralin Hall Lab: 303 Engel Hall Virginia Tech Department of Biochemistry 340 West Campus Dr. Blacksburg, VA 24061 jalem...@vt.edu | (540) 231-3129 http://www.thelemkullab.com ================================================== -- Gromacs Users mailing list * Please search the archive at http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting! * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists * For (un)subscribe requests visit https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or send a mail to gmx-users-requ...@gromacs.org.
