[gmx-users] itp and rtp file about polymer!!!!!!!!!!

[nanyu101]

Hi,
  I am very boring about how to create a topology of polyester.Would you please give me some advices on how to create a block for my polyester.CH3COOCH2CH2-(CH2COOCH(CH3))--CH2COOCH2CH3.I have created it rtp file:
[ ESF ]
 [ atoms ]
    C1  CH3    0.000     4
    C2    C    0.180     2
    O1   OS   -0.360     2
    C3  CS1    0.180     2
    O2   OM    0.000     3
    C4  CH3   0.000     1
 [ bonds ]
    C3   +C1
    C3    C4
    C3    O1
    O1    C2
    O2    C2
    C2    C1
 [ impropers ]
    C1    C2    O1    O2
[ ESL ]
 [ atoms ]
    C1   CH2   0.000     1
    C2     C   0.180     2
    O1    OS  -0.360     2
    C3   CS2   0.180     2
    O2    OM   0.000     3
    C4   CH3   0.000     4
 [ bonds ]
   -C3    C1
    C1    C2
    C2    O2
    O1    C2
    O1    C3
    C3    C4
 [ impropers ]
    C1    C2    O1    O2
[ EST ]
 [ atoms ]
    C1   CH2   0.000     1
    C2     C   0.180     2
    O1    OS  -0.360     2
    C3   CS1   0.180     2
    O2    OM   0.000     3
    C4   CH3   0.000     4
 [ bonds ]
   -C3    C1
    C1    C2
    C2    O1
    C2    O2
    O1    C3    
    C3    C4
 [ impropers ]
     C1    C2    O1    O2

ESF denotes the first monomer;EST denotes the middle of monomers;ESL denotes the last monomer;Should I do this three molecular type? By the way,How can I create its itp file?SHould I create three itp for each of them?If so,how to manage it?Thanks!!I am a novice in Gromacs.ANy detailed information is appreciated.

Best wishes,
Xianhui Wu 


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