The Bohr model for the hydrogen atom was among the earliest successes of quantum mechanics. It is obtained by application of classical energy and momentum concepts together with a nonclassical quantization rule. Rather amazingly, the Bohr model correctly describes the most important properties of the hydrogen atom, most importantly producing the Balmer formula, that are obtained using the full quantum mechanical machinery of the Schrödinger equation.

Balmer Formula, Bohr Radius, Hydrogen Atom, Principal Quantum Number, Rydberg, Rydberg Constant, Sommerfeld Model