Coulomb transition matrix with fractional values of interaction parameter

Leaning upon the specific Fock symmetry of the Coulomb interaction potential in the four-dimensional momentum space we perform the analytical solution of the Lippman-Schwinger equation for the Coulomb transition matrix in the case of negative energy at fraction values of the interaction parameter. Analytical expressions for the three dimensional and partial Coulomb transition matrix with simplest factional values of the interaction parameter are obtained.