We present the first threshold ion-pair production spectrum of a triatomic molecule. We have recorded the ion-pair yield spectrum and TIPP spectrum for the H 2 S f H + +SHion-pair channel using single-photon excitation. From the TIPP spectrum, we have determined the H-SH bond energy (31451 ( 4 cm -1 ) to unprecedented accuracy and demonstrated the formation of weakly bound H + -SH -(J′) ion-pair states, with rotational excitation of the SHanion up to J′ ) 4. The bound nature of these states, and the assigned spectrum that results from their field dissociation suggests that this technique can be applied to many other triatomic and larger polyatomic molecules in the future, leading to energetic, spectroscopic, and dynamical information about these species.

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Microstructured tungsten oxide (WO3) fabricated by laser‐irradiating tungsten foil in methanol has been developed as a substrate to soft‐ionize small‐molecular‐weight compounds by surface‐assisted laser desorption/ionization mass spectrometry. The material can be used to detect a wide variety of low molecular weight polar analytes in their protonated and deprotonated forms and non‐polar species as radical cations.

(2+1) resonantly enhanced multiphoton ionization (REMPI) spectra of ArXe have been recorded between ≊78 000 and 80 110.0 cm−1. Single isotopomer data was obtained using a time-of-flight (TOF) mass spectrometer. Vibrational analyses for several transitions involving ArXe excited states that dissociate to Ar(1S0)+Xe*(6p) are presented, in some instances, for the first time. In addition to vibrational numbering and constants, excited state symmetries were deduced from separate REMPI/TOF spectra recorded with linearly and circularly polarized light, while excited state bond lengths were derived from Franck–Condon factor calculations. Some of the excited states were found to have potential humps and/or unusual vibrational band intensity distributions. Where possible, the nature of the perturbations is discussed.

An experimental arrangement is described where a Babinet-Soleil compensator is inserted into the path of one of the three beams used for noncoplanar beam interference lithography. This birefringent element can change the phase of the beam so that either a positive two-dimensional pattern or an inverselike structure is generated in a photoresist without disturbing the mechanical geometry of the setup. Simulations are presented that confirm the validity of this approach. Large defect-free sample areas (>1 cm(2)) with submicrometer periodic patterns were obtained by expanding the laser beams used in the lithography experiment.

Mass-resolved two-photon ionization spectra of ArXe and KrXe have been recorded using both linearly and circularly polarized fundamental laser beams. From the resultant intensity changes, the published excited-state electronic symmetry assignments for the band systems of ArXe in the region of the Xe * 6s [1/2] o