Institute for Theoretical Atomic, Molecular and Optical Physics between AMO theory and experiment and promoting AMO theory within the general physics community. It has been involved in some capacity in most of the National Research Council target areas, i.e. precision measurements and tests of fundamental laws, ultracold physics, the development and application of ultra-intense, short wavelength light sources, ultra-fast quantum control of atoms, molecules and electrons, nanoscience, and quantum information science. The Institute is sponsored by the National Science Foundation, the Smithsonian Institution, the Center for Astrophysics and Harvard University. The Armstrong Report in 1987 on "The State of Theoretical Atomic, Molecular and Optical Sciences in the United
Atoms in molecules have a well-defined physical basis. QTAIM recovers the central operational concepts of the molecular structure hypothesis, that of a functional grouping of atoms with an additive and characteristic set of properties, together with a definition of the bonds that link the atoms and impart the structure. QTAIM defines chemical bonding and structure of a chemical system based on the topology of the electron density. In addition to bonding, AIM allows the calculation of certain physical properties on a per-atom basis, by dividing space up into atomic volumes containing exactly one nucleus, which acts as a local attractor of the electron