title: Fluorescence emission from photo-fragments after resonant S 2p excitations in H2S.
abstract: Visible-UV fluorescence emission of gas-phase hydrogen sulfide, H(2)S, has been studied at the S 2p edge with synchrotron radiation excitation. Dispersed fluorescence measurements in the wavelength range 300-900 nm were taken at several photon energies corresponding to the excitations of the S 2p electrons to the unoccupied molecular and Rydberg orbitals. The spectra reveal fluorescence from the H, S, S(+), HS and HS(+) photo-fragments. H is found to be the strongest emitter at Rydberg excitations, while the emission from S(+) is dominant at the molecular resonances and above the S 2p ionization thresholds. The intensities of hydrogen Lyman-alpha (122 nm), Balmer-alpha (656 nm), Balmer-beta (486 nm) transitions as well as the visible-UV total fluorescence yield (300-900 nm) and the total ion yield were measured by scanning the photon energy in small steps across the S 2p edge. The different Balmer lines show some sensitivity to the specific core excitations, which is, however, not so strong as that recently observed in the water molecule [E. Melero García, A. Kivimäki, L. G. M. Pettersson, J. Alvarez Ruiz, M. Coreno, M. de Simone, R. Richter and K. C. Prince, Phys. Rev. Lett., 2006, 96, 063003].
authors.affiliation: Royal Institute of Technology, Department of Physics, AlbaNova University Center, 10691 Stockholm, Sweden. gemma@atom.kth.se
authors.forename: G
authors.initials: G
authors.lastname: Vall-Llosera
authors.forename: E
authors.initials: E
authors.lastname: Melero García
authors.forename: A
authors.initials: A
authors.lastname: Kivimäki
authors.forename: E
authors.initials: E
authors.lastname: Rachlew
authors.forename: M
authors.initials: M
authors.lastname: Coreno
authors.forename: M
authors.initials: M
authors.lastname: de Simone
authors.forename: R
authors.initials: R
authors.lastname: Richter
authors.forename: K C
authors.initials: KC
authors.lastname: Prince