Atomic, molecular, and optical physics and chemical physics. Both subfields are primarily concerned with electronic structure and the dynamical processes by which these arrangements change. Generally this work involves using quantum mechanics. For molecular physics, this approach is known as quantum chemistry. One important aspect of molecular physics is that the essential atomic orbital theory in the field of atomic physics expands to the molecular orbital theory. Molecular physics is concerned with atomic processes in molecules, but it is additionally concerned with effects due to the molecular structure. Additionally to the electronic excitation states which are known from atoms, molecules are able to rotate and
Nuclear Power and the Environment radiation to aid in later chapters. The first half covers the basics on atoms such as: an atom consists of Neutrons, Protons, and Electrons; the atomic number of an atom determines the amount of protons in one atom; and that protons are roughly 2000 times heavier than electrons (see atom). The concept of radiation is introduced through ionization which is the process of adding one or more electrons to, or removing one or more electrons from, atoms or molecules, thereby creating ions. From there certain particles can cause ionization. The ionizing particles are alpha particles (a type of ionizing radiation