Structure, dynamics and quantum chaos in atoms and molecules under strong magnetic fields

Although studies on the interaction of atoms and molecules with external magnetic fields are more than 100 years old, beginning from the pre-quantum-mechanical days to the era of quantum mechanics, interest in the application of strong, static magnetic fields on atoms and molecules is only about three decades old. Although a great deal of insight has been obtained on the consequent changes in electronic structure and chemical bonds by such strong fields, the more realistic, dynamic, strong magnetic fields were not studied. Based on our own works in the last decade, we will discuss in this article how strong static as well as oscillating, strong magnetic fields on atoms and molecules affect electron density and chemical bonds. The dynamic fields generate completely new, hitherto unknown exciting phenomena. Our discussions will be based on three inter-linked, fundamental aspects of matter-external-magnetic-field interactions, viz., (1) action of static, strong magnetic fields as well as associated changes in electronic structure and the chemical bond, (2) Dynamics of electron density, and (3) Non-linear effects inherent in these interactions. Each aspect, although discussed separately for clarity, is a part of a larger intertwining picture.