[gmx-users] 1-4 interaction VS. normal Coulomb interaction

[xieyh at hkusua.hku.hk]

Dear all:

A simple question is needed to get a confirmation from you.

In .top file, I define a [ pairs ] section, which is related to 1-4 Vdws and
Coulomb interactions. In addition, as known, the non-bonded electrostatic
interactions are calculated based on cut-off distance. 

Now, I am confused with 1-4 and normal electrostatic interactions. In detail, 
1. Atoms listed in [ pairs ] will be dealt with 1-4 interactions, and between
the same pairs, the normal Coulomb interactions will also be calculated? In
other words, are both 1-4 interactions and normal electrostatic interactions
considered for these pairs?

2. Is the scaling factor "FudgeQQ" only useful in OPLS force field?


Thanks.



Xie Yinghong
Hong Kong Univ.