Dipole-bound anions of carbonyl, nitrile, and sulfoxide containing molecules

Abstract

Dipole-Bound Anions of 28 molecules containing either a carbonyl, nitrile, sulfoxide, or sulfite group were studied using Rydberg Electron Transfer (RET) reactions with rubidium atoms excited to ns 2S and nd 2D excited states. The electron affinity of each molecule was obtained from the Rydberg state, n*max, that gave the largest negative ion yield using the empirical relationship EA=23/n*max2.8 eV as well as from fitting the charge exchange profile to a theoretical curve crossing model. Electron affinities for the low dipole moment molecules (carbonyls) were also calculated from measurements of the electric field required to detach the electron from the anion. The dependences of the electron affinity upon dipole moment, polarizability, conformation, and geometry of the molecules are investigated. The effect of collision velocity on the creation of these anions is studied through the use of different carrier gases (H2, He, Ne, Ar, Kr, Xe) in the nozzle jet expansion. Competition between RET and collisional detachment is observed and discussed qualitatively

HIGH-ACCURACY QUARTIC FORCE FIELD CALCULATIONS FOR THE SPECTROSCOPIC CONSTANTS AND VIBRATIONAL FREQUENCIES OF 11A′l-C3H–: A POSSIBLE LINK TO LINES OBSERVED IN THE HORSEHEAD NEBULA PHOTODISSOCIATION REGION

“…However, this same process results in a veritable sea of elections that could attach to neutrals and actually lead to the creation of anions even in the Horsehead nebula PDR (Millar et al 2007). Additionally, many anions are known to be surprisingly stable (Hammer et al 2003;Simons 2008Simons , 2011Fortenberry & Crawford 2011b, 2011aFortenberry 2013), and electron attachment rates are also believed to be quite high in these regions (Millar et al 2007). Several anions have also been shown to possess dipolebound excited states, or threshold resonances, which may play a significant role in the creation and recreation of interstellar anions (Güthe et al 2001;Carelli et al 2013).…”

A multi-agent quantum Monte Carlo model for charge transport: Application to organic field-effect transistors

“…DBS was predicted to exist for neutral molecules with sufficiently large dipole moments (>2.5D) [130][131][132][133] and had been observed, [134][135][136][137][138] usually with very low binding energies. Excited DBSs near the detachment thresholds of anions were observed by Brauman and co-workers in photodetachment cross sections.…”

Excited State Trends in Bidirectionally Expanded Closed-Shell PAH and PANH Anions

“…3,4 However, some anions can bind an excess electron in a loosely bound, diffuse orbital where the positive end of the core neutral's dipole moment is large enough (in the vicinity of 2.5 D or greater) to retain the electron. [5][6][7][8] Such states are known for various organic molecular anions. 3,4,[9][10][11][12][13][14][15][16][17][18][19][20][21] Some of these so-called dipole-bound excited states have even been suggested to explain longstanding interstellar phenomena.…”