De Broglie’s theory of wave nature of electrons: Electron, like light has dual character (particle and wave like) de Broglie suggested the wave nature of electrons and derived the relation λ = h/p where λ is the wavelength and p the momentum of the electron and h is Plank’s constant. This relation is verified by interference and diffraction experiments with electrons.
Heisenberg’s uncertainty principle: It is impossible to find out simultaneously the exact position and exact velocity of a subatomic particle like electron since electron is very light and tiny particle. To observe an electron, a radiation of very short wavelength (i.e., of high energy) must be allowed to fall on it. The moment such a high energy radiation falls on an electron, its position is changed.
Uncertainty principle changed Bohr’s concept of stationary orbits: As the position and velocity of an electron cannot be measured simultaneously, it is not possible to assign a path or an orbit to an electron.
Orbital: is defined as three dimensional space around the nucleus of an atom where there is a maximum probability of finding an electron.
