Theoretical Atomic and Molecular Physics
My work over recent years has been mainly in two areas, cold atoms and transport properties of gases.
Metastable helium, being a novel companion to alkali atoms for cold-atom studies, possesses some 20 eV of internal energy and allows single-atom detection. Furthermore, the potential curves governing the relative motion of two metastable atoms are accessible to highly accurate ab initio calculation. Such calculations have been performed by the group of Gadéa (Toulouse). Using these potential curves, calculations on the scattering and photoassociation of metastable helium, including 3He, have been performed. The main findings concerning the scattering length and the near-dissociation binding energies have provided further stimulation to experimentalists working in this field. Related studies have led to the first prediction of very long-range bound states of 3He2.
Progress in understanding the complex behaviour of real gases demands an improved knowledge of their thermophysical properties such as viscosity and thermal conductivity. A new formulation, developed in collaboration with a group from Rostock, allows the calculation of thermophysical properties from potential surfaces for rigid molecules of arbitrary symmetry, particularly useful for predicting properties at high temperatures. Results of calculations on water and methane are currently being analysed.