[Openmd-users] Nearest neighbour treatment

[Dan Gezelter]

Brett,

There are parameters you can set up in the top of a forcefield file to control the scaling of non-bonded interactions between atoms that are involved in explicit short-range interactions. 

vdW-12-scale
vdW-13-scale
vdW-14-scale
electrostatic-12-scale
electrostatic-13-scale
electrostatic-14-scale

All of these default to zero if your forcefield doesn't set them, but if you look at the top of the Amber.frc file in the forceFields directory, you'll see a force field where the 14 interactions have both been set to non-zero values:

begin Options
      Name                    "Amber"
      vdW-14-scale            0.5         
      electrostatic-14-scale  0.83333333333333333
end Options

Glad to hear that OpenMD is scaling well!

Best regards,

 --Dan


On Aug 2, 2010, at 10:19 AM, Brett Donovan wrote:

> Hi Dan
> 
> Just another question about nearest neighbour treatment, given four
> atoms pair-wise bonded: 0,1,2,3, what non-bonded interactions are
> performed between these atoms?
> 
> Thanks
> 
> Brett
> 
> PS. BTW people are very impressed with the scaling abilities of OMD!

***********************************************
  J. Daniel Gezelter
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