[gmx-users] afm pull

[Robert Vacha]

Hi all,
  I have a problem with simple simulation using AFM pull code in version 3.1.5_pre1. 
My simulation consists of 4 atoms    
1SOL     KR    1   0.697   0.647  15.809   
2SOL     KR    2   0.697   0.647  15.282 
3DRG     AR    3   0.697   0.647  20.000
4DRG     AR    4   0.697   0.647  10.000 
in normal NVE simulation argons stay(cut off =1nm) and kryptons oscilate in Lennard-Jones potential. 
But, if I connect my two argons by afm, argons stay and do not move.
Could anyone give me some advice what can be wrong?
                                   
Thanks,
Robert Vacha

ps: afm parameters are
runtype                = afm 
reftype                = com_t0
reflag                 = 1
direction              = 0.0 0.0 1.0
pullrate               = 0.00000000000001
forceconstant          = 5000