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Liu T, Lester MI. Roaming in the Unimolecular Decay of syn-Methyl-Substituted Criegee Intermediates. J Phys Chem A 2023; 127:10817-10827. [PMID: 38109698 DOI: 10.1021/acs.jpca.3c05859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Alkene ozonolysis generates transient carbonyl oxide species, known as Criegee intermediates, which are a significant nonphotolytic source of OH radicals in the troposphere. This study demonstrates that unimolecular decay of syn-methyl-substituted Criegee intermediates proceeds via 1,4 H atom transfer to vinyl hydroperoxides, resulting in OH fission to O-O products or, alternatively, OH roaming to hydroxycarbonyl products. Newly generated Criegee intermediates are shown to yield hydroxycarbonyls with sufficient internal excitation to dissociate via C-C fission to acyl and hydroxymethyl (CH2OH) radicals. The stabilized Criegee intermediates and unimolecular products are rapidly cooled in a pulsed supersonic expansion for photoionization detection with time-of-flight mass spectrometry. CH2OH products are identified by 2 + 1 resonance-enhanced multiphoton ionization via the 3pz Rydberg state upon unimolecular decay of CH3CHOO, (CH3)2COO, (CH3)(CH3CH2)COO, and (CH3)(CH2═CH)COO (methyl vinyl ketone oxide). The stabilized Criegee intermediates are separately detected using 10.5 eV photoionization. This study provides the first experimental evidence of roaming in the unimolecular decay of isoprene-derived methyl vinyl ketone oxide and extends earlier studies that reported stabilized hydroxycarbonyl products.
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Affiliation(s)
- Tianlin Liu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
| | - Marsha I Lester
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States
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2
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Bross DH, Yu HG, Harding LB, Ruscic B. Active Thermochemical Tables: The Partition Function of Hydroxymethyl (CH2OH) Revisited. J Phys Chem A 2019; 123:4212-4231. [DOI: 10.1021/acs.jpca.9b02295] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David H. Bross
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Hua-Gen Yu
- Division of Chemistry, Department of Energy and Photon Sciences, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Lawrence B. Harding
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Branko Ruscic
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
- Consortium for Advanced Science and Engineering, The University of Chicago, Chicago, Illinois 60637, United States
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3
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Xie C, Malbon CL, Xie D, Yarkony DR, Guo H. Nonadiabatic Dynamics in Photodissociation of Hydroxymethyl in the 32A(3px) Rydberg State: A Nine-Dimensional Quantum Study. J Phys Chem A 2019; 123:1937-1944. [DOI: 10.1021/acs.jpca.8b12184] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Changjian Xie
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Christopher L. Malbon
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Daiqian Xie
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - David R. Yarkony
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
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4
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Xie C, Guo H. Active vs. spectator modes in nonadiabatic photodissociation dynamics of the hydroxymethyl radical via the 2 2A(3s) Rydberg state. J Chem Phys 2018; 148:044305. [PMID: 29390808 DOI: 10.1063/1.5017737] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The choice of the active degrees of freedom (DOFs) is a pivotal issue in a reduced-dimensional model of quantum dynamics when a full-dimensional one is not feasible. Here, several five-dimensional (5D) models are used to investigate the nonadiabatic photodissociation dynamics of the hydroxymethyl (CH2OH) radical, which possesses nine internal DOFs, in its lowest absorption band. A normal-mode based scheme is used to identify the active and spectator modes, and its predictions are confirmed by 5D quantum dynamical calculations. Our results underscore the important role of the CO stretching mode in the photodissociation dynamics of CH2OH, originating from the photo-induced promotion of an electron from the half-occupied π*CO antibonding orbital to a carbon Rydberg orbital.
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Affiliation(s)
- Changjian Xie
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
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Xie C, Malbon C, Yarkony DR, Guo H. Nonadiabatic photodissociation dynamics of the hydroxymethyl radical via the 22A(3s) Rydberg state: A four-dimensional quantum study. J Chem Phys 2017; 146:224306. [DOI: 10.1063/1.4985147] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Changjian Xie
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Christopher Malbon
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - David R. Yarkony
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, USA
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6
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Malbon CL, Yarkony DR. Multistate, multichannel coupled diabatic state representations of adiabatic states coupled by conical intersections. CH2OH photodissociation. J Chem Phys 2017; 146:134302. [DOI: 10.1063/1.4978708] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - David R. Yarkony
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, USA
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7
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Malbon CL, Yarkony DR. Nonadiabatic Photodissociation of the Hydroxymethyl Radical from the 22A State. Surface Hopping Simulations Based on a Full Nine-Dimensional Representation of the 1,2,32A Potential Energy Surfaces Coupled by Conical Intersections. J Phys Chem A 2015; 119:7498-509. [DOI: 10.1021/acs.jpca.5b00758] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Christopher L. Malbon
- Department
of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - David R. Yarkony
- Department
of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
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8
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Rodrigo CP, Zhou C, Reisler H. Accessing Multiple Conical Intersections in the 3s and 3px Photodissociation of the Hydroxymethyl Radical. J Phys Chem A 2013; 117:12049-59. [DOI: 10.1021/jp404552g] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Chirantha P. Rodrigo
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482,
United States
| | - Chuanchuan Zhou
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482,
United States
| | - Hanna Reisler
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482,
United States
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Ryazanov M, Rodrigo C, Reisler H. Overtone-induced dissociation and isomerization dynamics of the hydroxymethyl radical (CH2OH and CD2OH). II. Velocity map imaging studies. J Chem Phys 2012; 136:084305. [DOI: 10.1063/1.3685899] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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10
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Kamarchik E, Rodrigo C, Bowman JM, Reisler H, Krylov AI. Overtone-induced dissociation and isomerization dynamics of the hydroxymethyl radical (CH2OH and CD2OH). I. A theoretical study. J Chem Phys 2012; 136:084304. [DOI: 10.1063/1.3685891] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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11
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Samanta K, Yarkony DR. On the role of conical intersections and their local topography in the photodissociation of the 1-hydroxyethyl radical. Chem Phys 2010. [DOI: 10.1016/j.chemphys.2010.10.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Karpichev B, Koziol L, Diri K, Reisler H, Krylov AI. Electronically excited and ionized states of the CH2CH2OH radical: A theoretical study. J Chem Phys 2010; 132:114308. [DOI: 10.1063/1.3354975] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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13
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Reisler H, Krylov AI. Interacting Rydberg and valence states in radicals and molecules: experimental and theoretical studies. INT REV PHYS CHEM 2009. [DOI: 10.1080/01442350902989170] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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14
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Karpichev B, Edwards LW, Wei J, Reisler H. Electronic Spectroscopy and Photodissociation Dynamics of the 1-Hydroxyethyl Radical CH3CHOH. J Phys Chem A 2008; 112:412-8. [DOI: 10.1021/jp077213w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Boris Karpichev
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482
| | - Laura W. Edwards
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482
| | - Jie Wei
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482
| | - Hanna Reisler
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482
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15
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Wei J, Karpichev B, Reisler H. Unimolecular processes in CH2OH below the dissociation barrier: O–H stretch overtone excitation and dissociation. J Chem Phys 2006; 125:34303. [PMID: 16863346 DOI: 10.1063/1.2216703] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The OH-stretch overtone spectroscopy and dynamics of the hydroxymethyl radical, CH(2)OH, are reported in the region of the second and third overtones, which is above the thermochemical threshold to dissociation to H+CH(2)O (D(0)=9600 cm(-1)). The second overtone spectrum at 10 484 cm(-1) is obtained by double resonance IR-UV resonance enhanced multiphoton ionization (REMPI) spectroscopy via the 3p(z) electronic state. It is rotationally resolved with a linewidth of 0.4 cm(-1) and displays properties of local-mode vibration. No dissociation products are observed. The third overtone spectra of CH(2)OH and CD(2)OH are observed at approximately 13 600 cm(-1) by monitoring H-atom photofragments while scanning the excitation laser frequency. No double resonance REMPI spectrum is detected, and no D fragments are produced. The spectra of both isotope analogs can be simulated with a linewidth of 1.3 cm(-1), indicating dissociation via tunneling. By treating the tunneling as one dimensional and using the calculated imaginary frequency, the barrier to dissociation is estimated at about 15 200 cm(-1), in good agreement with theoretical estimations. The Birge-Sponer plot is linear for OH-stretch vibrations 1nu(1)-4nu(1), demonstrating behavior of a one-dimensional Morse oscillator. The anharmonicity parameter derived from the plot is similar to the values obtained for other small OH containing molecules. Isomerization to methoxy does not contribute to the predissociation signal and the mechanism appears to be direct O-H fission via tunneling. CH(2)OH presents a unique example in which the reaction coordinate is excited directly and leads to predissociation via tunneling while preserving the local-mode character of the stretch vibration.
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Affiliation(s)
- Jie Wei
- Department of Chemistry, University of Southern California, Los Angeles, CA 90089-0482, USA
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16
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Potter AB, Wei J, Reisler H. Photoinitiated Predissociation of the NO Dimer in the Region of the Second and Third NO Stretch Overtones. J Phys Chem B 2005; 109:8407-14. [PMID: 16851987 DOI: 10.1021/jp046226w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photofragment yield spectra and NO(X(2)Pi(1/2,3/2); v = 1, 2, 3) product vibrational, rotational, and spin-orbit state distributions were measured following NO dimer excitation in the 4000-7400 cm(-1) region in a molecular beam. Photofragment yield spectra were obtained by monitoring NO(X(2)Pi; v = 1, 2, 3) dissociation products via resonance-enhanced multiphoton ionization. New bands that include the symmetric nu(1) and asymmetric nu(5) NO stretch modes were observed and assigned as 3nu(5), 2nu(1) + nu(5), nu(1) + 3nu(5), and 3nu(1) + nu(5). Dissociation occurs primarily via Deltav = -1 processes with vibrational energy confined preferentially to one of the two NO fragments. The vibrationally excited fragments are born with less rotational energy than predicted statistically, and fragments formed via Deltav = -2 processes have a higher rotational temperature than those produced via Deltav = -1 processes. The rotational excitation likely derives from the transformation of low-lying bending and torsional vibrational levels in the dimer into product rotational states. The NO spin-orbit state distribution reveals a slight preference for the ground (2)Pi(1/2) state, and in analogy with previous results, it is suggested that the predominant channel is X(2)Pi(1/2) + X(2)Pi(3/2). It is suggested that the long-range potential in the N-N coordinate is the locus of nonadiabatic transitions to electronic states correlating with excited product spin-orbit states. No evidence of direct excitation to electronic states whose vertical energies lie in the investigated energy region is obtained.
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Affiliation(s)
- A B Potter
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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17
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Feng L, Wei J, Reisler H. Rotationally Resolved Infrared Spectroscopy of the Hydroxymethyl Radical (CH2OH)†. J Phys Chem A 2004. [DOI: 10.1021/jp040101+] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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18
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Feng L, Reisler H. Photodissociation of the Hydroxymethyl Radical from the 22A‘ ‘(3pz) State: H2CO and HCOH Products. J Phys Chem A 2004. [DOI: 10.1021/jp0479769] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Lin Feng
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482
| | - Hanna Reisler
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482
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19
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Feng L, Demyanenko AV, Reisler H. Competitive C–H and O–D bond fission channels in the UV photodissociation of the deuterated hydroxymethyl radical CH2OD. J Chem Phys 2004; 120:6524-30. [PMID: 15267543 DOI: 10.1063/1.1665880] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Photodissociation studies of the CH2OD radical in the region 28,000-41,000 cm(-1) (357-244 nm), which includes excitation to the 3s, 3p(x), and 3p(z) states, are reported. H and D photofragments are monitored by using resonance-enhanced multiphoton ionization (REMPI) from the onset of H formation at approximately 30,500 cm(-1) to the origin band region of the 3pz(2A")<--1 2A" transition at 41,050 cm(-1). Kinetic energy distributions P(ET) and recoil anisotropy parameters as a function of kinetic energy, beta(eff)(ET), are determined by the core sampling technique for the channels producing H and D fragments. Two dissociation channels are identified: (I) D+CH2O and (II) H+CHOD. The contribution of channel II increases monotonically as the excitation energy is increased. Based on the calculations of Hoffmann and Yarkony [J. Chem. Phys. 116, 8300 (2002)], it is concluded that conical intersections between 3s and the ground state determine the final branching ratio even when initial excitation accesses the 3px) and 3pz states. The different beta(eff) values obtained for channels I and II (-0.7 and approximately 0.0, respectively) are attributed to the different extents of out-of-plane nuclear motions in the specific couplings between 3s and the ground state (of A' and A'' symmetry, respectively) that lead to each channel. The upper limit to the dissociation energy of the C-H bond, determined from P(ET), is D0(C-H)=3.4+/-0.1 eV (79+/-2 kcal/mol). Combining this value with the known heats of formation of H and CH2OD, the heat of formation of CHOD is estimated at DeltaHf(0)(CHOD)=24+/-2 kcal/mol.
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Affiliation(s)
- Lin Feng
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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Matsika S, Yarkony DR. Beyond two-state conical intersections. Three-state conical intersections in low symmetry molecules: the allyl radical. J Am Chem Soc 2003; 125:10672-6. [PMID: 12940752 DOI: 10.1021/ja036201v] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using multireference configuration interaction expansions comprised of over 7 million configuration state functions, three-state conical intersections are reported for the closely spaced, spectroscopically observed (tilde)B(2A1), (tilde)C(2B1), and (tilde)D(2B2) states (in C(2v) symmetry) of the allyl radical. These conical intersections of states which were previously assigned as the 3,4,5(2)A states and are here reassigned as the 4,5,6(2)A states, are expected to be accessible using optical probes. This conclusion is obtained from the structure of the minimum energy point on the 4,5,6(2)A three-state conical intersection seam which is similar to the equilibrium structure of the ground (tilde)X(2A2) state and only 1.1 eV above the (tilde)D(2B2) state at its equilibrium geometry. The seam of three-state degeneracies joins two two-state seams of conical intersection, the 4,5(2)A and 5,6(2)A conical intersection seams. The energy of the minimum energy point on the 4,5(2)A two-state seam is only 0.15 eV above that of the (tilde)D(2B2) state at its equilibrium structure. Three-state intersections are also reported for the 3,4,5(2)A states.
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Affiliation(s)
- Spiridoula Matsika
- Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218, USA.
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21
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Feng L, Demyanenko AV, Reisler H. O–D bond dissociation from the 3s state of deuterated hydroxymethyl radical (CH2OD). J Chem Phys 2003. [DOI: 10.1063/1.1571526] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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22
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Matsika S, Yarkony DR. Accidental conical intersections of three states of the same symmetry. I. Location and relevance. J Chem Phys 2002. [DOI: 10.1063/1.1513304] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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23
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Feng L, Huang X, Reisler H. Photodissociative spectroscopy of the hydroxymethyl radical (CH2OH) in the 3s and 3px states. J Chem Phys 2002. [DOI: 10.1063/1.1498469] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Friedman RS, Podzielinski I, Cederbaum LS, Ryaboy VM, Moiseyev N. Vibronic Resonances Arising from Conically Intersecting Electronic States. J Phys Chem A 2002. [DOI: 10.1021/jp0136922] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Lorenz S. Cederbaum
- Theoretische Chemie, Physikalisch-Chemisches Institut Universität Heidelberg, D-6900 Heidelberg, Federal Republic of Germany
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25
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Hoffman BC, Yarkony DR. Photodissociation of the hydroxymethyl radical. I. The role of conical intersections in line broadening and decomposition pathways. J Chem Phys 2002. [DOI: 10.1063/1.1468882] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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26
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Conroy D, Aristov V, Feng L, Sanov A, Reisler H. Competitive pathways via nonadiabatic transitions in photodissociation. Acc Chem Res 2001; 34:625-32. [PMID: 11513569 DOI: 10.1021/ar970047y] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photodissociation processes of molecules and radicals involving multiple pathways and nonadiabatic crossings are studied using the photofragment imaging technique and the core-sampling version of time-of-flight spectroscopy. Capabilities and challenges are illustrated by two systems. The isocyanic acid system demonstrates how interactions among potential energy surfaces can change during dissociation. The hydroxymethyl photodecomposition system highlights Rydberg-valence interactions common in free radicals. The cross-fertilization between theory and experiment is emphasized.
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Affiliation(s)
- D Conroy
- Department of Chemistry, University of Southern California, Los Angeles, California 90089-0482, USA
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