Following laser irradiation of a flowing mixture of S2Cl2 and H2S at 308 nm to initiate the reaction of Cl+H2S, vibration-rotation resolved emission spectra of HCl(v=1,2) in the spectral region 2436-3310 cm(-1) are detected with a step-scan time-resolved Fourier-transform spectrometer. The Boltzmann-type rotational distributions of HCl(v=1) and HCl(v=2) yield rotational temperatures that decrease with reaction time; extrapolation to time zero based on data in the range 0.5-4.0 mus yields nascent rotational temperatures of 1250+/-70 K and 1270+/-120 K, respectively; an average rotational energy of 8.3+/-1.5 kJ mol(-1) is determined for HCl(v=1,2), much greater than a previous report. Observed temporal profiles of the vibrational population of HCl(v=1,2) are fitted with a kinetic model that includes formation and quenching of HCl(v=1,2) to yield a branching ratio of 0.14+/-0.01 for formation of HCl(v=2)/HCl(v=1) and a thermal rate coefficient of k(1)=(3.7+/-1.5)x10(-11) cm(3) molecule(-1) s(-1). Combining an estimate of the vibrational population of HCl(v=0) based on a surprisal analysis of previous investigations on the reaction Cl+D2S, we report a ratio of vibrational distributions of HCl(v=0):(v=1):(v=2)=0.41:0.52:0.07, which gives an average vibrational energy of 23+/-4 kJ mol(-1) for HCl. Internal energies, especially rotational energy, of HCl derived with this method is more reliable than with previous techniques; the fractions of available energy going into rotation and vibration of HCl are f(r)=0.12+/-0.02 and f(v)=0.33+/-0.06, respectively. (C) 2003 American Institute of Physics.