AMBER Archive (2008)

Subject: Re: AMBER: Explanation of the energy unit ?

From: David A. Case (
Date: Sun Sep 07 2008 - 17:12:22 CDT

On Sat, Sep 06, 2008, Marek Malư wrote:
> Let's assume that we have some molecular system Y and we for example
> calculate the total energy of this system. Lets say that result is
> X[kcal/mol].
> My only interpretation is that X is the energy in [kcal] of NA systems Y.
> So if I want energy of one system Y in [kcal] it is X/NA. Where NA is
> Avogadro constant.

This is correct. 1 cal = 4.184 J (exactly). See wikipedia (or other
places) for a discussion of its history and use.


The AMBER Mail Reflector
To post, send mail to
To unsubscribe, send "unsubscribe amber" (in the *body* of the email)