[gmx-users] Re: vaccum simulation error

[Dr. Vitaly Chaban]

>>
>> hi all,
>> i am trying to simulate polymer chains in solvent and vacuum media
>> using 45a3
>> forcefield. for vacuum simulation i used different md parameters
>> than that of
>> solvent media. first i put 100ps NVT and then 100ps NPT. i
>> sucessfully got NVT
>> done but for NPT i got following error ,
>>
>> WARNING 1 [file npt-pr.mdp, line unknown]:
>>  Turning off pressure coupling for vacuum system
>>
>>
>> NOTE 1 [file npt-pr.mdp, line unknown]:
>>  Tumbling and or flying ice-cubes: We are not removing rotation around
>>  center of mass in a non-periodic system. You should probably set
>>  comm_mode = ANGULAR.
>>
>> Too many warnings (1), grompp_mpicc terminated.
>> If you are sure all warnings are harmless, use the -maxwarn option.


How would you define a pressure in the sizeless box?



Dr. Vitaly V. Chaban
MEMPHYS - Center for Biomembrane Physics
Campusvej 55, 5230 Odense M, Kingdom of Denmark