Photoelectron–photofragment coincidence (PPC) spectroscopy is used to study the photodetachment, photodissociation, and dissociative photodetachment (DPD) of I2Br−, IBr2−, I2Cl−, and ICl2− at 266 nm. The mixed trihalides are asymmetric analogs of the well-studied I3− anion, with distinguishable dissociation asymptotes and the potential for selective bond breaking. The high beam energy PPC spectrometer used in this study couples an electrospray ionization source, a hexapole accumulation ion trap, and a linear accelerator to produce a 21 keV beam of a particular trihalide. Total, stable, and dissociative photoelectron spectra have been recorded for all the anions, except ICl2− that does not photodetach at 266 nm. A bound ground state (X) is observed for all the anions, and a dissociative first excited (A) state is also seen for I2Br− and I2Cl− at low electron kinetic energies (eKE). A 258 nm photoelectron spectrum recorded for I2Br− and I2Cl− rules out autodetachment of a dipole-bound state as the origin of the low eKE feature. The threshold detachment energy (TDE) of I2X− to the X state of the radical is similar to I3−, whereas the TDE to the radical A state increases with substitution of iodine for a lighter halogen. Two-body DPD is observed for I2Br− and I2Cl−, resulting in IBr/ICl + I + e−. For IBr2− and ICl2−, the charge symmetric three-body photodissociation of [Br–I–Br]− and [Cl–I–Cl]− is seen yielding Br + Br and Br + Br*, and Cl + Cl and Cl + Cl* neutral fragments. Evidence for the minimum energy anion structure is observed in all cases, where the iodine atom is located at the center of the trihalide.
Skip Nav Destination
CHORUS
Article navigation
7 August 2020
Research Article|
August 03 2020
Photoelectron–photofragment coincidence spectroscopy of the mixed trihalides Available to Purchase
J. A. Gibbard
;
J. A. Gibbard
a)
Department of Chemistry and Biochemistry, University of California, San Diego
, 9500 Gilman Dr., La Jolla, California 92093-0340, USA
a)Author to whom correspondence should be addressed: [email protected]
Search for other works by this author on:
E. Castracane
;
E. Castracane
Department of Chemistry and Biochemistry, University of California, San Diego
, 9500 Gilman Dr., La Jolla, California 92093-0340, USA
Search for other works by this author on:
R. E. Continetti
R. E. Continetti
Department of Chemistry and Biochemistry, University of California, San Diego
, 9500 Gilman Dr., La Jolla, California 92093-0340, USA
Search for other works by this author on:
J. A. Gibbard
a)
Department of Chemistry and Biochemistry, University of California, San Diego
, 9500 Gilman Dr., La Jolla, California 92093-0340, USA
E. Castracane
Department of Chemistry and Biochemistry, University of California, San Diego
, 9500 Gilman Dr., La Jolla, California 92093-0340, USA
R. E. Continetti
Department of Chemistry and Biochemistry, University of California, San Diego
, 9500 Gilman Dr., La Jolla, California 92093-0340, USA
a)Author to whom correspondence should be addressed: [email protected]
J. Chem. Phys. 153, 054304 (2020)
Article history
Received:
May 18 2020
Accepted:
July 16 2020
Citation
J. A. Gibbard, E. Castracane, R. E. Continetti; Photoelectron–photofragment coincidence spectroscopy of the mixed trihalides. J. Chem. Phys. 7 August 2020; 153 (5): 054304. https://doi.org/10.1063/5.0014253
Download citation file:
Pay-Per-View Access
$40.00
Sign In
You could not be signed in. Please check your credentials and make sure you have an active account and try again.
Citing articles via
CREST—A program for the exploration of low-energy molecular chemical space
Philipp Pracht, Stefan Grimme, et al.
DeePMD-kit v2: A software package for deep potential models
Jinzhe Zeng, Duo Zhang, et al.
Related Content
Two- and three-body photodissociation dynamics of diiodobromide (I2Br−) anion
J. Chem. Phys. (April 2011)
Self-assembling of the neutral intermediate with chemically bound argon in photoexcited van der Waals complex Ar–I2
J. Chem. Phys. (September 2021)
Internal energy dependence of the photodissociation dynamics of O3− using cryogenic photoelectron-photofragment coincidence spectroscopy
J. Chem. Phys. (September 2017)
Photoelectron imaging of PtI2− and its PtI− photodissociation product
J. Chem. Phys. (April 2022)
Photoelectron spectroscopy of high temperature vapors. V. HeI spectra of GaX3 and InX3 (X = Cl, Br, I)
J. Chem. Phys. (July 1974)