# sdens

This keyword specifies the number of quadrature points per Å2 to use in calculation surface terms (e.g., molecular surface, solvent accessible surface). This keyword is ignored when srad is 0.0 (e.g., for van der Waals surfaces) or when srfm (elec) is `spl2` (e.g., for spline surfaces). The syntax is:

    sdens {density}

where `density` is a floating point number indicating the number of grid points per Å-2. A typical value is 10.0.

Note

There is a strong correlation between the value used for the sphere density, the accuracy of the results, and the APBS calculation time.