The classical view of the atom had a glaring difficulty. Classically, an electron continuously emitting energy should spiral into the nucleus. Bohr took this a step further, hypothesizing that the energy E is the difference in the atom’s energy when an electron moves from one orbit to another.įigure 3.
However, he did recognize that the frequency of emitted radiation is determined by E = hf (actually, f = E/h). Interestingly, Bohr didn’t believe in photons when he developed the quantum view of the atom. Five years later Einstein proposed not only that material energy is quantized, but that light itself exists as quantum lumps, or “corpuscles,” later named photons. With the constant of proportionality h (Planck’s constant) we have the familiar E = hf. In 1900 Max Planck postulated that the energy of a radiated quantum of energy is proportional to the frequency of radiation: E ~ f.
