ented by a list of atoms. (structure)</span>
<a name="l00075"></a>00075 <span class="comment">        Perform a simple sum of atoms mass.</span>
<a name="l00076"></a>00076 <span class="comment">  </span>
<a name="l00077"></a>00077 <span class="comment">   ## PARAMETRES:</span>
<a name="l00078"></a>00078 <span class="comment">        @ s_atm *atoms : List of atoms structures</span>
<a name="l00079"></a>00079 <span class="comment">        @ int natoms   : Number of atoms</span>
<a name="l00080"></a>00080 <spa