Photoelectron spectroscopy of unstable molecules

The gas-phase chemiionization reaction between samarium and oxygen atoms: A theoretical study

“…A variety of these reactions involving lanthanides and actinides have been studied experimentally in the gas phase, [5][6][7] but this is the first time that one of these reactions has been investigated with quantum chemical methods. The mechanism of the SmϩO chemiionization reaction has been established from the computed potential curves of SmO and SmO ϩ and the states involved have been identified.…”

“…The reaction is exothermic, and can therefore be observed experimentally, if the dissociation energy of the metal oxide produced is greater than the adiabatic ionization energy of the neutral metal oxide. Unfortunately, although qualitative potential energy curves can be drawn to explain the production of ions and electrons for an MϩO chemiionizatiion reaction, [5][6][7] no electronic structure calculations have yet been made for the states involved for any MϩO reactions studied experimentally. This is almost certainly because most of the metals ͑M͒ for which this form of ionization has been observed are lanthanides and actinides, in which the MO and MO ϩ species are difficult to treat theoretically, not least because the metals have electronic configurations with unfilled f shells and give rise to a number of low-lying states in MO and MO ϩ .…”

“…13 MϩO chemiionization reactions, such as the SmϩO associative ionization reaction, have also been considered as a way of monitoring atomic oxygen in the upper atmosphere. [5][6][7] Although lanthanide monoxides ͑LnO͒ have been the subject of extensive theoretical and experimental studies, there are no ab initio studies on the electronic structures of SmO and SmO ϩ . This is because of the complexity of the electronic structures of these species, in particular the high angular momentum and spin multiplicity of the low-lying states involved.…”

An investigation of the SO(X3Σ-) molecule by multiphoton ionization spectroscopy

“…A preliminary analysis of the band shown in figure 2(c) in terms of a (3 + 1) 32-,--3Z transition [59], made before the polarization behaviour of this band had been investigated, gave a poor fit of the experimental transition energies. The subsequent analysis in terms of a (2 + 2) process via the B3Z , v' = 8 intermediate state gave a much better fit of the experimental line positions.…”

High‐resolution Photoelectron Spectroscopy

“…The method provides information on the electronic structure of molecules and on the vibrational structure of molecular ions, and is extremely powerful HRS071 High-resolution photoelectron spectroscopy 12 in detecting subtle changes in the electronic structure within classes of molecules and in clusters. It has also been used to gain information on anions (see, for instance, Engelking and Lineberger (1977) for an early application), neutral radicals (Baker et al 1990) and cations that are very difficult to study with other spectroscopic methods. UPS also represents a very important technique to study molecules adsorbed on surfaces, liquids and even liquid jets (Faubel et al 1998).…”