INTEGRAL EXPRESSIONS OF THE SMALL-ANGLE SCATTERING CORRELATION-FUNCTION DERIVATIVES

The integral expression of the nth derivative of the SAS correlation-f unction (gamma(r)) is reported. It is the average, throughout the samp le interface, of the loop integral of a vectorial field A(n) over arro w pointing right (r(j)(l)). All the A(n) over arrow pointing right (r( j)(l))'s, with n greater-than-or-equal-to 3, are recursively obtained by appropriate differentiation of A(2) over arrow pointing right (r(j) (l)), whose explicit expression is given in terms of the parametric eq uations of the interface. For very smooth interface it results that al l the CF even-derivatives are null at the origin.