Basic assumption that collisions are binary results in severe problems when trying to take multiple interactions into account. Also, in simulating crystalline materials the selection process of the next colliding lattice atom and the impact parameter p always involve several parameters which may not have perfectly well defined values, which may affect the results 10–20% even for quite reasonable-seeming choices of the parameter values.
The fundamental assumption that collisions are binary leads to significant challenges when dealing with multiple interactions. Similarly, in simulating crystalline materials, selecting the next colliding lattice atom and determining the impact parameter p often involves numerous parameters whose values may not be perfectly defined, potentially affecting results by 10–20%.