Observation of an Excited Dipole-Bound State in a Diatomic Anion

Lu, Yunqing; Tang, Rulin; Ning, Chuangang

doi:10.1021/acs.jpclett.1c01726

Cited by 24 publications

(29 citation statements)

References 69 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…DBS has been ubiquitously found in a variety of chemical or biological systems, ranging from small organic to large biological molecules or clusters. [14][15][16][17][18][19][20][21] Recent spectroscopic studies have suggested that the DBS could be a primary candidate for the carrier of the diffuse interstellar species and/or the interstellar PAH anions, giving the enormous astrochemical implication. [22][23][24][25] The anion chemistry/physics provoked by the electron-attachment is ubiquitously found not only in the atmospheric or interstellar species but also in a variety of biological/chemical processes such as photosynthesis, 26 destruction/relaxation of DNA bases, [27][28][29] or signaling of the fluorescent proteins.…”

mentioning

confidence: 99%

Experimental Observation of the Resonant Doorways to Anion Chemistry: Dynamic Role of Dipole-Bound Feshbach Resonances in Dissociative Electron Attachment

et al. 2022

View full text Add to dashboard Cite

Anion chemical dynamics of autodetachment and fragmentation mediated by the dipole-bound state (DBS) have been thoroughly investigated in a state-specific way for the first time by employing the picosecond time-resolved or the nanosecond frequency-resolved spectroscopy combined with the cryogenically cooled ion trap and velocity-map imaging techniques. For the ortho-, meta-, or para-iodophenoxide anion (o-, m-, or p-IPhO -), the C-I bond rupture giving the anionic iodide (I -) fragment occurs via the nonadiabatic transition from the DBS to the nearby valence-bound states (VBS) of the anion where the vibronic coupling into the S1 (πσ*) state (which is repulsive along the C-I bond extension coordinate) should be largely responsible. The dynamic details are governed by the isomer-specific nature of the potential energy surfaces in the vicinity of the DBS-VBS curve crossings, as manifested in the huge different chemical reactivity of o-, m-, or p-IPhO -. It is confirmed here that the C-I bond dissociation is mediated by DBS resonances, providing the foremost evidence that the metastable DBS plays the essential role as the doorway into the anion chemistry especially of the dissociative electron attachment (DEA). The fragmentation channel is dominant when it is mediated by the DBS resonances located below the electron-affinity (EA) threshold, whereas it is kinetically adjusted by the competitive autodetachment process when the DBS resonances lying above EA convey the electron to the valence orbitals. The product yield of the C-I bond cleavage is strongly mode-dependent as the rate of the concomitant autodetachment is much influenced by the characteristics of the individual vibrational modes, paving a new way of the reaction control of the anion chemistry.

show abstract

mentioning

confidence: 99%

Experimental Observation of the Resonant Doorways to Anion Chemistry: Dynamic Role of Dipole-Bound Feshbach Resonances in Dissociative Electron Attachment

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Compared to the average VDEs of 4.44 and 4.70 eV for band systems A and B, the resonating photodetachment energies of 5.21 and 5.30 eV are more than 0.6 eV higher in energy, which is far beyond the typical range of vibronic couplings. Therefore, vibronic couplings in the Ω = 3/2 DBS of either σ-type or the recently observed π-type, 39,40 both of which have much smaller binding energies, can be excluded as the explanation for the observed resonances. The resonant photodetachment energies, on the other hand, are close to the EBE of the Ω = 1/2 band system, which exhibits maxima at approximately 5.4 and 5.6 eV for A* and B*, respectively (Figure 4a).…”

mentioning

confidence: 89%

Observation and Exploitation of Spin–Orbit Excited Dipole-Bound States in Ion–Molecule Clusters

Cao

Zhang

Yuan

et al. 2021

J. Phys. Chem. Lett.

View full text Add to dashboard Cite

We report an observation of spin−orbit excited dipole-bound states (DBSs) in arginine−iodide complexes (Arg•I − ) by using temperaturedependent, wavelength-resolved "iodide-tagging" negative ion photoelectron spectroscopy. The observed DBSs are bound to the spin−orbit excited I( 2 P 1/2 ) level of the neutral Arg•I complex in zwitterionic conformations and identified based on the resonant enhancement due to spin−orbit electronic autodetachment from the I( 2 P 1/2 ) DBS to the I( 2 P 3/2 ) neutral ground state. The observed DBS binding energies are correlated to the dipole moments of neutral Arg•I isomers and tautomers. This work thus demonstrates a new and generic spectroscopic approach to identify ion−molecule cluster conformations based on their distinguishable dipole moments.

show abstract

“…25 However, in contrast to neutral and cationic species, which support many bound excited states, anions rarely have bound excited states. [26][27][28] Among promising exceptions 25,29 are C − 2 and BN − , which are isoelectronic to SiO + . Molecular anions of alkali metals were also investigated computationally 30,31 , how-ever, the authors were not able to establish whether their electronic states were bound or metastable with respect to electron detachment.…”

Section: Introductionmentioning

confidence: 99%

On the prospects of optical cycling in diatomic cations: Effects of transition metals, spin-orbit couplings, and multiple bonds

Wójcik

Hudson

Krylov

2022

Preprint

View full text Add to dashboard Cite

Molecules with optical cycling centers (OCCs) are highly desirable in the context of fundamental studies as well as applications (e.g., quantum computing) because they can be effectively cooled to very low temperatures by repeated absorption and emission (hence, cycling). Charged species offer additional advantages for experimental control and manipulation. We present a systematic computational study of a series of diatomic radical-cations made of a d-block metal and a p-block ligand, that are isoelectronic (in their valence shell) to the successfully laser-cooled neutral molecules. Using high-level electronic structure methods, we characterize state and transition properties of low-lying electronic states and compute Franck-Condon factors. The computed branching ratios and radiative lifetimes reveal that the electronic transitions analogous to those successfully used in the laser cooling of neutral molecules are less than optimal in the cations. We propose alternative transitions suitable for optical cycling and highlight trends that could assist future designs of OCCs in charged or neutral molecules.

show abstract

Observation of an Excited Dipole-Bound State in a Diatomic Anion

Cited by 24 publications

References 69 publications

Experimental Observation of the Resonant Doorways to Anion Chemistry: Dynamic Role of Dipole-Bound Feshbach Resonances in Dissociative Electron Attachment

Experimental Observation of the Resonant Doorways to Anion Chemistry: Dynamic Role of Dipole-Bound Feshbach Resonances in Dissociative Electron Attachment

Observation and Exploitation of Spin–Orbit Excited Dipole-Bound States in Ion–Molecule Clusters

On the prospects of optical cycling in diatomic cations: Effects of transition metals, spin-orbit couplings, and multiple bonds

Contact Info

Product

Resources

About