[gmx-users] problems in simulation

[Alok]

hi gromax users,
i am new in this field
i have started simulation work of lipid molecules
but i am experencing some problems
first i downloaded the dppc128.pdb and dppc.itp files form peter tieleman
site
when generating topology and gro file by using pdb2gmx program i am
getting following prompt
               'fatal error DPP molecule not found in .rtp file'
 dppc.itp file is kept in home directory with dppc128.pdb and not in
gromax topology folder(/usr/
share/local/gromacs/top)
is this the reason for problem

another query is how are box dimensions determined
lastly dppc128.pdb contains both lipids and water are both defined  in
same group or separate
groups are needed.

thanks in advance
bye
alok jain


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ALOK JAIN
M.TECH BSBE
C-106 HALL-7
IIT KANPUR
KANPUR-208016
INDIA
PH 94155-40594
EMAIL-alokjain at iitk.ac.in
      alokjain16 at yahoo.com
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