RE: Unit of Force constant of position restraint

From: Vermaas, Joshua (
Date: Mon Mar 18 2019 - 11:59:53 CDT

Its (kcal/mol)/A^p. The "per-atom" part just means that you have extra flexibility to define restraints that are different for different regions for your system, depending on the value in the .pdb column. Since you set the value to 1 for your whole system with consexp 4, the k is 1 (kcal/mol)/A^4.


On 2019-03-17 22:26:04-06:00 wrote:

Dear all,
What is the unit of the force constant used in position restraint.
"constraints" has the potential k(x-x0)^p. And the description says Per-atom values for k can be defined in consfile/conskcol. If I set the value in the conskcol (k) to 1 and the consexp (p) to 4, what would be the unit of k?
I thought it would be something like kcal/mol/Angstrom^4, but the "per-atom" value confused me.
Thank you

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