Law
Hund's Rule
For a given electron configuration, the lowest energy term is the one with the greatest value of spin multiplicity.
Quantum Chemistry
Field: Quantum Chemistry
Sequence of Expressions
In the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels.
It is impossible to determine simultaneously both the position and momentum of a particle with arbitrary precision.
The motion of atomic nuclei and electrons in a molecule can be separated because nuclei are much heavier and move much slower than electrons.