From:	"James J. P. Stewart" <jstewart*at*us.fujitsu.com>
Date:	Wed, 28 Apr 2004 09:55:48 -0600
Subject:	Re: CCL:Calculation of an angle

Given the three distances between each pair of atoms, use the familiar
equation:

c^2 = a^2 + b^2 - 2abCos(c)

or Cos(c) = (a^2 + b^2 - c^2)/(2ab)

Given Cos(c) take the inverse to get the angle c.

Jimmy

At 02:03 PM 4/21/2004, you wrote:
>Dear All,
>
>I am looking for an equation to calculate an angle from the cartesian
>coordinates of the 3 atoms making this angle.
>


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