Emission spectra and potentials of the 0+u and 1u states of Xe2

An extensive series of time-resolved measurements of Xe*2 second continuum emission spectra has been completed to reveal the spectra of the relaxed individual emitting states. Optical pumping of high-pressure Xe by a short-pulse F2 laser at 157.6 nm was used together with a gated optical multichannel analyzer detector or monochromator and boxcar integrator to time resolve the emission bands of the 0+u and 1u states. The bands are broader than expected and have center wavelengths close together. Curve fits to the data yield the parameters for the fully relaxed states: 1u:λc =171.4±0.6 nm, Δλ=12.2±0.2 nm and 0+u: λc =170.4±0.6 nm, Δλ=13.1±0.3. Temperature-dependent measurements from 246 to 413 K show a rapidly broadening band width with temperature. The results provide the first definitive measurement of the individual excimer emissions from the Xe2(0+u) and Xe2(1u) states. From these measurements and the known ground-state potential, we have derived 0+u and 1u potentials that reproduce the emission bands and temperature dependence very well.