Experimental Oscillator Strength of OH, 2Σ+→2Π, by a Chemical Method

The line absorption method is used to determine the oscillator strength of OH, 2Σ—2Π, in a discharge-flow system. OH is made quantitatively by the rapid reaction H+NO2→OH+NO. f values for the unresolved Q1—4 doublet and P1—2 line are calculated from the measured absorption of these lines. On the well-supported assumption of Doppler-shaped emission and absorption lines and on the basis of experimental information on the translational temperature of emitting and absorbing OH molecules, a band oscillator strength, f00, of 7.1±1.1×10—4 is reported for the (0, 0) band. Application of corrections for thermochemistry and for vibration—rotation interaction to reported f values leads to improved agreement and suggests an f00 near 8×10—4.