TITLE:

Laser spectroscopy of crossed molecular beams: the dissociation energy of BaI from energy-balance measurements

AUTHORS:

Vaccaro, P.H.; Zhao, D.; Tsekouras, A.A.; Leach, C.A.; Ernst, W.E.; Zare, R.N.; Dept. of Chem., Stanford Univ., CA, USA

PUBLICATION:

Journal of Chemical Physics, vol.93, no.12, p. 8544-56, 15 Dec. 1990 48 Refs.

ABSTRACT:

Through application of energy-balance arguments to the crossed-beam reaction Ba(¹S₀)+HI(X¹Ó⁺) to BaI(X²Ó⁺) + H(²S_1/2), a lower limit for the BaI bond dissociation energy is determined to be D₀⁰(BaI) ~76.8±1.7 kcal/mol (3.33±0.07 eV). Based on the upper bond of D₀⁰(BaI) <=78.5±0.5 kcal/mol, as determined from earlier predissociation studies (M.A. Johnson, J. Allison, and R.N. Zare, J. Chem. Phys. 85, 5723 (1986)), the authors recommend a BaI bond strength of 77.7±2.0 kcal/mol (3.37±0.09 eV). This dissociation energy is more than 5 kcal/mol higher than the previously accepted value of D₀⁰(BaI) as derived from mass spectrometric measurements.