How did Humans and Chimps diverge as a species?

Well apparently not even the top scientists who spend their career researching this exact question can come up with a definitive answer, so I don’t feel too bad in saying I’m really not sure..I do think it is an interesting idea that chimps and humans could have diverged through interbreeding and thus creating different lineages from this hybrid. I can see how this would be a plausible conclusion since at that stage I imagine the differences weren't so distinguishable that it would make them incompatible mates for the time. I would think that the different physical and mental development and the needs of this crossbreed would set them enough apart from their predecessors to support the divergence of these species, over time becoming more and more distinct.