Parity (physics) of formula_59, The overall parity of a many-particle system is the product of the parities of the one-particle states. It is -1 if an odd number of particles are in odd-parity states, and +1 otherwise. Different notations are in use to denote the parity of nuclei, atoms, and molecules. Atomic orbitals have parity (-1), where the exponent ℓ is the azimuthal quantum number. The parity is odd for orbitals p, f, ... with ℓ = 1, 3, ..., and an atomic state has odd parity if an odd number of electrons occupy these orbitals. For example, the ground state of
Institute for Theoretical Atomic, Molecular and Optical Physics Institute for Theoretical Atomic, Molecular and Optical Physics The Institute for Theoretical Atomic, Molecular and Optical Physics (ITAMP) is an international scientific learned society based at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. It was established in 1988 to alleviate a perceived shortage of theorists in atomic, molecular, and optical physics (AMO) at major universities throughout America. AMO concerns the study of matter-matter and light-matter interactions at the scale of one or a few atoms. The stated objectives of the Institute are: The objectives are tackled by fostering an intellectually stimulating environment, developing pioneering research areas, facilitating closer interactions