[gmx-users] Particle type 'B' in topology file?

[cdalgicdir]

Hi all,

I have performed a simulation where for an atomtype, I accidentally put 
'B' instead of 'A' which stands for 'atom'. The manual doesn't mention 
any 'B''s for particle type, (it mentions A,S,V and D). I have then 
corrected this (replaced B with A) and obtained a totally different 
configuration. I now wonder what have I used as particle type for the 
particle I have defined as type 'B'?

What does "B" as particle type stand for?

Atomtypes section of my topology file:

[ atomtypes ]
;name   mass    charge  ptype   V(c6)   W(c12)
     X          1         0.000     A        1.0       1.0
     Y          1         0.000     B        1.0       1.0

Thanks,

Cahit