 are evaluated.

<P>
<PRE>
  TOLERANCES accCoul &lt;integer accCoul default 8&gt;
</PRE>

<P>
Screening away needless computation of the XC functional (on the grid)
due to negligible density is also possible with the use of,
<PRE>
  TOLERANCES tol_rho &lt;real tol_rho default 1e-10&gt;
</PRE>
XC functional computation is bypassed if the corresponding density
elements are less than <code>tol_rho</code>.

<P>
A screening parameter, <code>radius</code>, used in the screening of the
Becke or Delley spatial weig