Probing the accuracy of the isomerization energy of the 3-D morphed potential of Ar–HBr

Investigations of the lowest Σ-bending vibrations of Ar–DBr (v = 0) and Ar–HBr (v = 1) are reported using a co-axially configured submillimeter supersonic jet spectrometer. The v = 1 spectra were obtained using glow discharge excitation. Analyses of hyperfine substructure in these spectra provide accurate molecular parameters for Ar–DBr and Ar–BrD isomeric states, direct determination of their corresponding isomerization energies, and respective parameters in the v = 1 HBr stretching vibration of the Ar–HBr isotopomer. This experimental data provides a sensitive probe of the relative energies of potential minima for previously determined 3-D Ar–HBr morphed potential and compared with results from extrapolations to the CCSD(T)/CBS limit.