I really don't believe that photons can be particles. Supposedly the photoelectric effect "proves" they are. I believe that electrons are emitted as a result of short-distance penetration of the wave front into the metal, disturbing the bonds. This would also fit the known fact that the frequency of light must be above a certain value or electrons are not emitted. I'm betting that the minimum frequency corresponds to the longest wavelength that can "fit between" the lattice structure. Comments please?