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.

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