In a traditional Monte Carlo (MC) model the carrier preserves its band identity during the free flight between scatterings. However, this assumption may not be valid in semiconductor materials with complex unit cell. A new model is needed where the traditional way to use classical equations during the free flight between scattering is replaced by a fully quantum mechanical model of the Bloch carrier dynamics between scattering events. In this work we present such a model along with simulated results of the hole initiated impact ionization coefficients of 4H-SiC