orbitale

OBS: La notion d'orbitale a remplacé celle d'orbite, propre au modèle planétaire de Bohr, lorsque fut reconnue l'impossibilité d'attribuer des trajectoires aux électrons atomiques.

CONT: ""orbital theory"": The quantum theory of matter applied to the nature and behavior of the electron, either in single atoms (atomic orbital) or in united atoms (molecular orbital). ... In simple language, the orbital theory considers the electron not as a particle, but as a three-dimensional wave that can exist at several energy levels; its exact location and position in the ""shell"" (which in most elements is a group of orbitals) cannot be precisely determined, but only predicted by the laws of mathematical probability. The orbital levels and the movement of electrons within them are expressed by wave functions and quantum numbers. The probability that an electron will be found in a given volume (i.e., the square of the one-electron wave function) is called the orbital of that electron, and the shape of the orbital is defined by surfaces of constant probability (i.e. spheres and doughnut-shaped ellipses). The electron orbital, described in terms of probability, is like a cloud, with indefinite boundaries.