<title>potlist</title>
<h3><center><font color=#brown >Potential Subroutines</h3>
</center></font><hr>
In the usual implementation of <a href=closecoupled.html>close coupled</a> methods the
 interaction potential <i>V(R)</i> is expanded as in a set of products of functions of the internal
degrees of freedom, multiplied by coefficients which depend on the separation coordinate <i>R</i>,
namely 


 <p><i><ul>V(R,q)</i> = <img src=sigma18.gif align=bottom>  
<i>V<sub><img src=lambda10.gif></sub></i>(<i>R</i>) 