S ECOND P OSTULATE OF Q UANTISATION Of all the postulates, Bohr made in his model of the atom, perhaps the most puzzling is his second postulate. It states that the angular momentum of the electron orbiting around the nucleus is quantised (that is, L n = nh/ ; n = , , …). Why should the angular momentum have only those values that are integral multiples of h/ ? The French physicist Louis de Broglie explained this puzzle in , ten years after Bohr proposed his model.
We studied, in Chapter , about the de Broglie’s hypothesis that material particles, such as electrons, also have a wave nature. C. J. Davisson and L.
H. Germer later experimentally verified the wave nature of electrons