Atomic, molecular, and optical physics electron is treated quantum mechanically. In low speed collisions the approximation fails. Classical Monte-Carlo methods for the dynamics of electrons can be described as semi-classical in that the initial conditions are calculated using a fully quantum treatment, but all further treatment is classical. Atomic, Molecular and Optical physics frequently considers atoms and molecules in isolation. Atomic models will consist of a single nucleus that may be surrounded by one or more bound electrons, whilst molecular models are typically concerned with molecular hydrogen and its molecular hydrogen ion. It is concerned with processes such as ionization, above threshold ionization and excitation
Ugo Fano Fano spent 1936–37 with Werner Heisenberg in Leipzig. In 1939, he married Camilla Lattes, also known as "Lilla", a teacher who would collaborate with him in a well-known book on atomic and molecular physics, "Physics of Atoms and Molecules" (1959). Appendix III of this book presents an elementary description of the collision of two charged particles, which was used by Richard Feynman in lectures that have been published as "". An expanded version of this book was subsequently published as "Basic Physics of Atoms and Molecules" (1972). Later that year, he immigrated to the United States due to increasing antisemitic