15min:

LECHENG WANG, DAIQIAN XIE, School of Chemistry and Chemical Engineering, Nanjing University, No.22 Hankou Road, Nanjing, Jiangsu, China, 210093 ; HUI LI, ROBERT J. LE ROY AND PIERRE-NICHOLAS ROY, Guelph-Waterloo Centre for Graduate Work in Chemistry and Biochemistry, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.

High resolution infrared spectra of an N₂O molecule seeded in ultra-cold helium custers have been reported by two groups.^,~ Early simulations of N₂O--(He)_n clusters^, were performed using potential energy surfaces (PESs) for which the dopant N₂O molecule was frozen at its equilibrium geometry. Since the evolution of the shift of the ₃ band-origin of N₂O provides a key link to bridge the gap between micro and macro world, a new 3D PES was generated which incorporated the asymmetric-stretch Q₃ vibrational motion of the N₂O.~ Bosonic PIMC simulations based on this surface were then used to study rotational dynamics, and energetic and superfluid properties of N₂O--(He)_n clusters. The evolution of the calculated shifts agree reasonably with the experimental results, but some quantitative discrepancies remain. To address this problem, a new four-dimensional N₂O--He PES has now been obtained which also takes account of the change in the average value of the Q₁ symmetric-stretch coordinate on excitation of ₃. It has been fitted to a generalized MLR functional form which imposes better long-range behaviour. Results obtained using this new surface will be presented.