title: Interatomic potential parameters of CdHe van der Waals complex derived from excitation spectrum of the C1 1(51P1)<--X10+(51S0) vibrational transition.
abstract: The first time observed excitation spectrum of the C(1)1(5(1)P(1))<--X(1)0+(5(1)S(0)) transition in CdHe van der Waals molecules is reported. Vibrational spectrum in the UV region (2286.0-2296 A) was excited in a continuous molecular-jet-expansion beam of CdHe seeded in helium using an in-house-built nitrogen-dye laser system. The excitation spectrum exhibits two vibrational components (v'<--v''=0) highly broadened by means of unresolved rotational structure and some additional contributions of "hot-bands" components (v'<--v''=1). The last effect is due to an extremely small separation of the vibrational levels in the ground X(1)0+ state of the CdHe molecule, where v'=0 vibrational level is separated from v''=0 by merely 6.0 cm(-1). It follows therefore that even in an extremely cold environment (T(v) approximately 10K) of a jet-expansion beam the population of v''=1 level is feasible, due to some residual collisions, and hence the v'<--v'=1 transitions are highly probable. The assignment of vibrational bands and numerical analysis of the spectrum was based and obtained with the aid of a rigorous computer simulation of the C(1)1<--X(1)0+ transition including the impact of rotational structure and hot-bands contributions. As a result we obtained optical potential parameters of the C(1)1(5(1)P(1)) state of CdHe molecule which are further discussed in terms of our recent (and only existing) experimental results regarding the X(1)0+, B1(5(3)P(1)) and A0+(5(3)P(1)) states of CdHe as well as in terms of ab initio calculations results.
authors.affiliation: Department of Physics, University of Windsor, Windsor, Ontario, Canada. mczajko@uwindsor.ca
authors.forename: M A
authors.initials: MA
authors.lastname: Czajkowski
authors.forename: W
authors.initials: W
authors.lastname: Kedzierski
authors.forename: J
authors.initials: J
authors.lastname: Koperski
mesh_terms: D002104:Cadmium / Q000737:chemistry*; D003198:Computer Simulation; D006371:Helium / Q000737:chemistry*; D007834:Lasers; D013050:Spectrometry, Fluorescence; D014466:Ultraviolet Rays
chemical_list: D002104:Cadmium; D006371:Helium