SINGULAR PARTS OF THE RELATIVISTIC FREE-FREE NON-DIPOLE
                       MATRIX ELEMENTS

            A.V.Korol$^{\ast\sharp}$   and  Igor A.Solovjev$^\ast$ 

$\ast$ Russian Maritime Technical University, St Petersburg, Russia 198262 
$\sharp$ Institut fur Theoretische Physik der Universitat Frankfurt am 
   Main, 60054 Frankfurt/M, Germany

The singular parts of the free-free single-photon matrix elements are 
exactly calculated for the first time for the case of relativistic 
projectile scattering in the field of a short-range potential.
The use of the obtained results for the approximate evaluation of 
many-photon relativistic matrix elements is discussed.