The radial hamiltonians for the X-1 Sigma(+) and B-1 Sigma(+) states of HCl

All literature vibration-rotational acid pure rotational transition energie s for the ground X(1)Sigma(+) electronic state of (HCl)-Cl-35, (HCl)-Cl-37, (DCl)-Cl-35, and (DCl)-Cl-37, along with the entire collection of electron ic B(1)Sigma(+) --> X(1)Sigma(+) emission data for the four isotopomers, ha ve been used in a least-squares fit of compact analytic Born-Oppenheimer po tential functions for the B(1)Sigma(+) and X(1)Sigma(+) electronic states. Additional functions related to the adiabatic and nonadiabatic corrections have also been determined. Separate least-squares fits were made according to the hamiltonian operators of J. K. G. Watson (J. Mel. Spectrosc. 80, 411 (1980)) and R. M. Herman and J. F, Ogilvie (Adv. Chem, Phys. 103, 187 (199 8)). The results from the separate analyses demonstrate clearly that the tw o hamiltonian operators are essentially equivalent, both achieving equally satisfactory representations of the spectral data, and furnishing virtually identical Born-Oppenheimer potential functions. Fully quantum-mechanical v ibrational eigenvalues and rotational perturbation series parameters B-v-O- v are presented for the lower levels of the X(1)Sigma(+) ground state for w hich infrared and/or microwave data are available (v(n) less than or equal to 7 for (HCl)-Cl-35 and (HCl)-Cl-37, v(n) less than or equal to 10 for (DC l)-Cl-35 and (DCl)-Cl-37). These parameters collectively reproduce the corr esponding spectroscopic line positions included in our fit to within the un certainties Of the measurements, (C) 2000 Academic Press.