Excited-State Absorption Spectrum ofF2+Centers and theH2+Molecular-Ion Model

Five principal transitions, three of which from the first excited state, have been measured in absorption for the ${F_2}^{+}$ center in KF. With one significant exception, these data are in essential agreement with predictions of the simple ${\mathrm{H}}_2^{+}$ molecular-ion model. The measurements were made by way of a novel optical pumping technique, which allows for direct, accurate determination of band strengths and shapes, even in the presence of strong overlapping absorptions by other species.