About calculation of the electric field in cpptraj

[pengfeili1]

Hi Dan,

Sorry for getting back to you so late. Can you help to add a function into cpptraj to calculate the electric field of certain groups on a certain atom or the center of certain atoms?

The command can be like that:

efield [out ] [mass] [scale14 <scale14_factor>]

It means to calculate electric field generated by on . If is a group, it means to calculate the electric generated by on the geometry center of mask2. And if [mass] specified, it means to calculate the electric generated by on the mass weighted geometry center of .

The data in the output file is similar to the format of the output of the distance or angle values.

One thing I suggest you to do is that if there are any atoms in also in or they have bond or angle interaction with atoms in , these atoms can be omit during the calculation. While the scale14_factor is used to scale the 1-4 electric interactions (default can be the AMBER default value as 1/1.2, if someone want to consider the full 1-4 electric interactions, he/she can set that value as 1).

Thanks! Pengfei