  The problem of finding of analytical gradients (derivatives over atoms
coordinates) of solvation energies can be decomposed on two subtasks: at the
first stage we search for parameters of the superficial devices (three
coordinates, three components of normal vector and square) and their
derivatives; at the second stage we differentiate energy and we express it
through derivative of the matrixes featuring a problem. But these derivatives
of matrix elements can be expressed through derivatives of parameters of
surface meshes of SES (solvent excluded surface) or SAS (solvent accessible
surface). The purpose of the given paper is finding of these analytical
gradients of the parameters of the surface meshes.
