EFFECTS OF 3-BODY (AXILROD-TELLER) FORCES ON THE CLASSICAL AND QUANTUM BEHAVIOR OF RARE-GAS TRIMERS

We have studied the structure and dynamics of nonrotating rare-gas tri mers bound by a potential that combines two-body Lennard-Jones interac tions and three-body Axilrod-Teller (triple dipole) interactions. Both classical and quantum trimers are examined. We investigate the onset and development of chaotic dynamics in the classical clusters by compu ting the Liapunov exponents associated with various phase space trajec tories. In our studies of the quantum clusters, we examine the structu re of the vibrational eigenstates, the statistical properties of the d istribution of energy levels, and the average cluster structure at fin ite temperatures. Both avenues of research are principally aimed at un derstanding the effect of the three-body term on the clusters' behavio r. We find that the three-body term gives rise to an integrable or nea rly integrable component of phase space that is associated with the cl usters' linear configuration and that manifests itself in both the cla ssical and quantum properties of the trimers. The finite temperature s tructures predicted for quantum Ne, clusters suggest that over the ran ge of parameters considered here, these clusters are sufficiently delo calized that properties associated with the linear configuration shoul d be readily observable, even at very low temperatures.