Theoretical investigations of molecular triple ionization spectra

Abstract

Articles you may be interested inPotential energy surface for and pure rotational spectra of isotopomeric Cl2-Ar van der Waals complexes Triple ionization of molecular systems is investigated theoretically by means of the three-particle propagator. This enables us to efficiently calculate the very dense triple ionization spectra. To be able to interpret these spectra an atomic three-hole population analysis is developed which provides information about the charge distribution in the molecular trication. In exemplary applications on CO and a series of fluorides the use of the approach is demonstrated. A large number of triply ionized electronic states are energetically accessible in the available particle impact ionization experiments and it is shown that many of these states contribute to the observations. Triply ionized states are also produced by Auger decay. In particular, shake-off satellite lines of molecular Auger spectra can be reproduced using the triple ionization energies from the propagator calculation and an estimate of the transition rates based on the three-hole population analysis. In general a dramatically growing complexity of the triple ionization spectra with increasing molecular size is demonstrated. In spite of this complexity the three-hole population analysis is of valuable help for the interpretation of the spectra and often a simple picture in terms of various hole-localization patterns arises.

Generation, Stability, and Reactivity of Small, Multiply Charged Ions in the Gas Phase

“…Surprisingly, also the number of theoretical studies on small trications is quite limited given the unusual bonding features typical for some of these systems. Note, however, that for trications a sufficient description of correlation effects in the computational studies becomes increasingly difficult and the number of low-lying states grows rapidly. , …”

“…Except for atoms, the generation of small trications is much more challenging than that of dications, because third ionization energies are rather huge (often >30 eV) and, as a consequence of the stronger Coulomb repulsion, most molecular trications are unstable and expected to dissociate spontaneously. 44 No surprise, the majority of the diatomic trications do indeed exhibit entirely repulsive potential energy curves. Only very few long-lived trications of small or moderate size have so far been examined experimentally (Table 2).…”

Highly excited electronic states of molecular clusters and their decay

“…The reason for the lack of decay channels in the HF dication becomes obvious when looking at the energetics of a possible decay. Using the ADC͑2͒ method for the evaluation of the three-particle Green's function 69 we have calculated the manifold of triply ionized states. These states are the potential final states for the decay of the dicationic states by electron emission.…”

[MLn]2+ doubly charged systems: modeling, bonding, life times and unimolecular reactivity

“…104 This is, however, in contrast with the scarce number of examples in the literature reporting the detection of diatomic trications involving transition metals, for instance [TiF] 3+ , 105 or tricharged complexes where transition metals and main group elements are coordinated to a small number (n = 2-6) of aprotic coordinating ligands, such as dimethylsulfoxide (DMSO), pyridine or acetonitrile. 27,106 In general, the huge third and fourth IEs, strong coulomb repulsions together with the difficulties inherent in properly describing a large number of low-lying electronic states 107 or the modeling of heavy elements complicate both the preparation and theoretical description of tri-and tetracations. In this sense, although some diatomic and small polyatomic triply charged species have been detected and theoretically characterized, further efforts are needed to deepen understanding into the nature of multiply charged species.…”