skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Low-lying vibronic level structure of the ground state of the methoxy radical: Slow electron velocity-map imaging (SEVI) spectra and Köppel-Domcke-Cederbaum (KDC) vibronic Hamiltonian calculations

Journal Article · · Journal of Chemical Physics
DOI:https://doi.org/10.1063/1.4984963· OSTI ID:1369391
ORCiD logo [1]; ORCiD logo [2];  [3];  [4]; ORCiD logo [5]
  1. Univ. of California, Berkeley, CA (United States)
  2. The Johns Hopkins Univ., Baltimore, MD (United States)
  3. Univ. of California, Berkeley, CA (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States)
  4. Univ. of Florida, Gainesville, FL (United States)
  5. Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
+ Show Author Affiliations

A joint experimental and theoretical study is reported on the low-lying vibronic level structure of the ground state of the methoxy radical using slow photoelectron velocity-map imaging spectroscopy of cryogenically cooled, mass-selected anions (cryo-SEVI) and Köppel-Domcke-Cederbaum (KDC) vibronic Hamiltonian calculations. The KDC vibronic model Hamiltonian in the present study was parametrized using high-level quantum chemistry, allowing the assignment of the cryo-SEVI spectra for vibronic levels of CH3O up to 2000 cm-1and of CD3O up to 1500 cm-1above the vibrational origin, using calculated vibronic wave functions. The adiabatic electron affinities of CH3O and CD3O are determined from the cryo-SEVI spectra to be 1.5689 ± 0.0007 eV and 1.5548 ± 0.0007 eV, respectively, demonstrating improved precision compared to previous work. Experimental peak splittings of <10 cm-1are resolved between the e1/2and e3/2components of the 61and 51vibronic levels. A pair of spin-vibronic levels at 1638 and 1677 cm-1were predicted in the calculation as the e1/2and e3/2components of 62levels and experimentally resolved for the first time. The strong variation of the spin-orbit splittings with a vibrational quantum number is in excellent agreement between theory and experiment. The observation of signals from nominally forbidden a1vibronic levels in the cryo-SEVI spectra also provides direct evidence of vibronic coupling between ground and electronically excited states of methoxy.

Research Organization:
SLAC National Accelerator Lab., Menlo Park, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
AC02-76SF00515; CHE-1361031; AC02-05CH11231; FG02-07ER15884
OSTI ID:
1369391
Alternate ID(s):
OSTI ID: 1369081; OSTI ID: 1458498
Journal Information:
Journal of Chemical Physics, Vol. 146, Issue 22; ISSN 0021-9606
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 15 works
Citation information provided by
Web of Science

References (41)

Methoxy formation in the reaction of CH3O2 radicals with NO journal June 1986
Free jet-cooled laser-induced fluorescence spectrum of methoxy. 1. Vibronic analysis of the ~A and ~X states journal October 1988
The electron affinities of O, Si, and S revisited with the photodetachment microscope journal May 2005
Laser photodetachment electron spectrometry of methoxide, deuteromethoxide, and thiomethoxide: Electron affinities and vibrational structure of CH 3 0, CD 3 0, and CH 3 S journal September 1978
Geometries of the methoxy radical (X 2E and A 2A1 states) and the methoxide ion journal February 1974
Photodissociation spectroscopy and dynamics of CH 3 O and CD 3 O journal September 1997
Isomer-specific vibronic structure of the 9-, 1-, and 2-anthracenyl radicals via slow photoelectron velocity-map imaging journal January 2016
Analytic energy derivatives for ionized states described by the equation‐of‐motion coupled cluster method journal November 1994
Photoelectron imaging: an experimental window into electronic structure journal January 2009
Rovibronic analysis of the laser induced fluorescence excitation spectrum of the jet-cooled methoxy radical journal May 1997
On the Behavior of Cross Sections Near Thresholds journal May 1948
Slow photoelectron velocity-map imaging spectroscopy of cold negative ions journal December 2012
General contraction of Gaussian basis sets. I. Atomic natural orbitals for first‐ and second‐row atoms journal April 1987
Stimulated emission pumping spectroscopy of CH 3 O ( X̃   2 E , ν 6 ): New observations on the Jahn–Teller effect journal March 1993
Jahn-Teller effect in CH 2 DO/CHD 2 O(X̃2E): Vibronic coupling of all vibrational modes journal June 2013
Perturbative calculation of spin-orbit splittings using the equation-of-motion ionization-potential coupled-cluster ansatz journal November 2008
A model spin-vibronic Hamiltonian for twofold degenerate electron systems: A variational ab initio study of X̃ 2E CH3O• journal January 2005
Inverting ion images without Abel inversion: maximum entropy reconstruction of velocity maps journal January 2014
Theoretical study of the Jahn–Teller effect in X̃ 2E CH3O journal March 2000
Cooling of large molecules below 1 K and He clusters formation journal May 2000
Quantitative insights about molecules exhibiting Jahn-Teller and related effects journal October 1998
Laser excitation and emission spectroscopy of the methoxy radical in a supersonic jet journal December 1993
Gaussian basis sets for use in correlated molecular calculations. I. The atoms boron through neon and hydrogen journal January 1989
Infrared absorption of CH3O and CD3O radicals isolated in solid para-H2 journal April 2015
Jet-Cooled Laser-Induced Fluorescence Spectroscopy of Cyclohexoxy: Rotational and Fine Structure of Molecules in Nearly Degenerate Electronic States journal August 2014
Two‐dimensional imaging of state‐selected photodissociation products detected by multiphoton ionization journal July 1987
Methoxyl radical reactions in atmospheric chemistry journal November 1975
Velocity map imaging of ions and electrons using electrostatic lenses: Application in photoelectron and photofragment ion imaging of molecular oxygen journal September 1997
The spectroscopic characterization of the methoxy radical. I. Rotationally resolved Ã A21–X̃ E2 electronic spectra of CH3O journal February 2009
The ν 3 Fundamental in NO 3 Has Been Seen Near 1060 cm –1 , Albeit Some Time Ago journal July 2012
Efficient and accurate approximations to the molecular spin-orbit coupling operator and their use in molecular g-tensor calculations journal January 2005
Vibronic analysis of the A ̃→ X ̃ laser‐induced fluorescence of jet‐cooled methoxy (CH 3 O) radical journal December 1993
Slow Electron Velocity-Map Imaging of Negative Ions: Applications to Spectroscopy and Dynamics † journal December 2008
Slow electron velocity-map imaging photoelectron spectra of the methoxide anion journal July 2006
Quantitative vibronic coupling calculations: the formyloxyl radical journal February 2011
The spectroscopic characterization of the methoxy radical. II. Rotationally resolved Ã A21-X̃ E2 electronic and X̃ E2 microwave spectra of the perdeuteromethoxy radical CD3O journal February 2009
Rotation–vibration state resolved unimolecular dynamics of highly vibrationally excited CH 3 O ( X ̃  2 E ). I. Observed stimulated emission pumping spectra journal September 1994
Photoelectron spectroscopy of CH3O− and CD3O− journal August 1998
Electron spin resonance studies of radical trapping in the radiolysis of organic liquids. I. Evidence for the primary formation of the methoxy radical in methanol journal November 1972
Vibronic structure of alkoxy radicals via photoelectron spectroscopy journal January 2000
Fluorescent spectra from ethyl nitrate. Part 1.—Supposed emissions from alkoxy radicals and NO 2 journal January 1953

Cited By (2)

Probing alkenoxy radical electronic structure using anion PEI spectroscopy journal January 2019
Laser-induced fluorescence and dispersed-fluorescence spectroscopy of the Ã2E−X̃2A1 transition of jet-cooled calcium methoxide (CaOCH 3 ) radicals journal October 2019

Similar Records

Isomer-specific vibronic structure of the 9-, 1-, and 2-anthracenyl radicals via slow photoelectron velocity-map imaging
Journal Article · Wed Jan 20 00:00:00 EST 2016 · Proceedings of the National Academy of Sciences of the United States of America · OSTI ID:1369391
+2 more
Vibrationally Resolved O 1{ital s} Photoelectron Spectrum of CO{sub 2}: Vibronic Coupling and Dynamic Core-Hole Localization
Journal Article · Fri Aug 01 00:00:00 EDT 1997 · Physical Review Letters · OSTI ID:1369391
+4 more
Fluorescence depletion spectroscopy for mapping dark vibronic levels in the A{sup 2}A{sub 1} state of the methoxy radical
Conference · Tue Dec 31 00:00:00 EST 1996 · OSTI ID:1369391

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY