Symmetry in atomic and molecular systems

AbstractSymmetry is used to define alternative categorizations to which real atomic and molecular systems may correspond. By constructing idealized models to correspond to limiting cases, it becomes possible to decide what are the best approximations and starting points for making mathematical representations of the real systems. This is illustrated with two examples: atoms with two valence electrons, and multidimensional potentials surfaces of atomic clusters. In the first example, the question is whether an independent-particle, quantum analogue of a solar system or a collective, rotor-vibrator model is more appropriate. In the second example, the problem is finding enough about the multidimensional potential to describe the dynamics of the atomic motion, without becoming overwhelmed with irrelevant data