# What are the Bohr's postulates?

Apr 24, 2015

If I remember correctly, Bohr postulated that:

1] The Orbits permitted for an electron in a atom are Quantized, meaning that only discrete orbits, corresponding to discrete energy levels, are allowed. In these orbits the electron does not emit energy (it is a stationary state). The electron can emit or absorb energy by jumping from an orbit to another;

2] Classical mechanics works for the "motion" in the orbitals BUT do not apply to the "jumps" between orbitals;

3] The "jump" from an allowed orbit to another involves the release or absorption of energy in the form (Einstein): $E = h \cdot \nu$ where $h$ is Plank's Constant and $\nu$ the frequency;

4] The allowed orbitals are characterized by quantized values of orbital angular momentum $L$: $L = n \frac{h}{2 \pi}$ with $n =$ angular momentum quantum number.

{Ref: H. C. Ohanian. Physics 2nd ed. London, WW Norton, 1985]