 electron configuration. In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule or other physical structure in atomic or molecular orbitals.One for example, the electron configuration of the neon atom is 1s2 to s2p6, using the notation explained below.Electronic configurations describe each electron as moving independently in an orbital, in an average field created by all other orbitals. Mathematically, configurations are described by Slater determinants or configuration state functions. According to the laws of quantum mechanics, for systems with only one electron, an energy is associated with each electron configuration and, upon certain conditions, electrons are able to move from one configuration to another by the emission or absorption of a quantum of energy, in the form of a photon.Knowledge of the electron configuration of different atoms is useful in understanding the structure of the periodic table of elements. This is also useful for describing the chemically bonds that hold atoms together. In bulk materials, this same idea helps explain the peculiar properties of lasers and semiconductors.