Abstract:

　　It is well known that a molecule is made of two types of charged particles, i.e. electrons and nuclei. These charged particles are not at rest but are moving, in a molecule, even at the absolute zero temperature. One may therefore expect that the origin of various molecular properties such as reactivity and biological activity can be traced back to the electron and nuclear motions and their changes. Such electron and nuclear motions can directly be observed by using electron and nucleus momentum spectroscopies, respectively, which are the complete electron analogue of the well-known X-ray and neutron Compton scattering. This Lecture begins with an overview of the subject, emphasizing its significance and scope. If time is allowed, our recently started project with momentum-space wavefunctions is also discussed, which aims to develop a new approach for predicting relative drug strength and identifying the key molecular orbitals that govern the drug reaction mechanism.