Time-resolved dissociation of bromonaphthalene ion studied by TPIMS and TRPD. Heat of formation of naphthyl ion

Hydrogenation and Charge States of PAHsPAHs in Diffuse Clouds. I. Development of a Model

“…After the work of Neusser and coworkers in 1986 on the benzene cation Kiermeir, & Neusser 1986), new experiments (Ku hlewind, have been carried out on the same system by Klippenstein, Faulk, & Dunbar (1993). Extensions to naphthalene, azulene, anthracene, phenanthrene, and pyrene cations have been made recently by Lifshitz and coworkers (Ho et al 1995 ;Gotkis et al 1993aGotkis et al , 1993bLing, Gotkis, & Lifshitz 1995 ;Ling, Martin, & Lifshitz 1997 ;Ling & Lifshitz 1998). In addition, another study involving many PAHs, ranging from benzene to coronene cations, has been carried out by Jochims et al (1994).…”

Radiative Association Kinetics and Binding Energies of Chromium Ions with Benzene and Benzene Derivatives

“…As examples, we cite the method of dissociative photoionization in an ion trap, which alleviates kinetic shift problems by allowing the energized near-threshold ions a long time to complete their dissociation; − and the method of rate−energy curve extrapolation, which proceeds by plotting out the dissociative rate−energy curve and extrapolating to the (unobservable) threshold at which the dissociation rate goes to zero. This can be done via photodissociation ,,, or via photoelectron−photoion coincidence (PEPICO) ionization. , In a similar spirit, the present paper offers an illustration of another route to circumventing these kinetic shift problems and obtaining binding energies for large ion−neutral complexes; in this case, the strategy focuses on the association kinetics to form the complex, an approach we have termed the radiative association (RA) kinetics method. This RA kinetics approach has been employed recently by our group to estimate binding energies for various complexes, , including both metal-ion complexes − and nonmetal-containing systems. − …”

Spectroscopic Evidence for a Triplet Ground State in the Naphthyl Cation

“…Electron donation of solvent molecules into the vacant σ‐orbital stabilizes the singlet relative to the triplet, which is indeed borne out by DFT calculations 16. Gas‐phase studies are thus required to evaluate the intrinsic stability of both spin states and while various mass‐spectrometric studies on C 10 H 7 + have been reported,15, 20, 21 they do not probe its (electronic) structure.…”

“…Analogously, homolytic bond cleavage in the C 10 H 7 Br + radical cation would lead to the triplet naphthyl cation. However, most gas‐phase reactivity studies involving the naphthyl cation have largely ignored possible implications of the different spin states20, 21 or simply assumed both states to occur 15. Moreover, H‐atom abstraction (HAA) from the benzene cation was first assumed to produce the (higher‐energy) triplet phenyl cation,27 but later studies suggested that an intersystem crossing occurs on the dissociation pathway, rapidly converting the system to the (lower‐energy) singlet state 6.…”

“…The naphthyl cation (C 10 H 7 + ) is generated by ArF laser photoionization of bromonaphthalene (C 10 H 7 Br) vapor and concomitant relaxation by CBr bond cleavage. The appearance energy of C 10 H 7 + is about 12 eV,20 so that the absorption of two 193 nm photons provides sufficient energy. Both 1‐ and 2‐bromonaphthalene isomers were used as precursor.…”