Erratum: A comparative theoretical analysis of the photochemistry of the methyl radical and related systems [J. Chem. Phys. <b>8</b>
                  <b/>, 2049 (1984)]

Yu, H. T.; Sevin, A.; Kassab, E.; Evleth, E. M.

doi:10.1063/1.447760

Cited by 13 publications
(18 citation statements)

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“…10 At 193.3 nm there are three energetically allowed dissociation pathways, two involving the loss of an H-atom and one involving the elimination of H 2 . Orbital correlations in the dissociation ~f the methyl radical were first examined theoretically by Yu et al 4 In agreement with the earlier postulation of Herzberg, the B-state was found to correlate with the formation of singlet methylene, CH 2 (a 1 A1), and the ground state methyl radicals correlate to two asymptotic dissociation channels,…”

Section: Introductionsupporting
confidence: 58%

“…The beam was measuredin situ and had a velocity of -3600 mls with a FWHM of -15%. The pulsed beam was twice collimated to an angular divergence of 2° and crossed at a right angle with the output of a Lambda-Physik EMG 202 MSC excimer laser which was operated 4 at the ArP transition (193.3 nm). The 5-30mJ/pulse output was focussed to a 2x4 mm spot in the interaction region using a spherical lens (f=30 em).…”

Section: Methodsmentioning
confidence: 99%

“…2 .3 This is somewhat surprising in light of the considerable attention given to the analogous A-states of NH 3 and H 2 0. 4 The ultraviolet spectroscopy of the methyl radical was first examined by Herzberg and Shoosmith 5 and the transition originating at 216 nm was assigned to an excitation of the unpaired 2pz electron to a 3s Rydberg orbital. The broadening of the CH 3 transition was attributed to a rapid predissociation of the excited state due to H-atom tunnelling.…”

Section: Introductionmentioning
confidence: 99%

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Photodissociation dynamics of the methyl radical 3s Rydberg state
North
¹
,
Blank
²
,
Chu
³

et al. 1995
The Journal of Chemical Physics
33
2
6
0
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The photodissociation dynamics of methyl radical have been investigated at 193.3 nm using photofragment translational spectroscopy. The formation of CH2 and H(2S) was the only dissociation pathway observed. Although it is not possible to assign the spin state of the methylene unambiguously, we believe that methylene is produced predominately in the ã 1A1 excited state. The translational energy distribution of the products is peaked at ∼13 kcal/mole which is consistent with the magnitude of the exit barrier on the excited state potential energy surface. The breadth of the distribution suggests that the methyl radicals dissociate from a wide range of geometries. From the photofragment angular distribution an anisotropy parameter of β=−0.9±0.1 was determined.
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Section: Introductionsupporting
confidence: 58%

Section: Methodsmentioning
confidence: 99%

Section: Introductionmentioning
confidence: 99%

See 1 more Smart Citation
Photodissociation dynamics of the methyl radical 3s Rydberg state
North
¹
,
Blank
²
,
Chu
³

et al. 1995
The Journal of Chemical Physics
33
2
6
0
View full text Add to dashboard Cite
The photodissociation dynamics of methyl radical have been investigated at 193.3 nm using photofragment translational spectroscopy. The formation of CH2 and H(2S) was the only dissociation pathway observed. Although it is not possible to assign the spin state of the methylene unambiguously, we believe that methylene is produced predominately in the ã 1A1 excited state. The translational energy distribution of the products is peaked at ∼13 kcal/mole which is consistent with the magnitude of the exit barrier on the excited state potential energy surface. The breadth of the distribution suggests that the methyl radicals dissociate from a wide range of geometries. From the photofragment angular distribution an anisotropy parameter of β=−0.9±0.1 was determined.
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“…6 This electronic transition has also been studied using the multiphoton ionization method by Welge et al 7 and Lin et al 8 Predissociation dynamics of the 3s Rydberg state has been investigated by Westre et al 9 and Settersten et al, 10 the predissociation lifetime of the ͑000͒ level is determined to be about 60 fs, indicating that the predissociation of the 3s state is extremely fast. Orbital correlations in the dissociation of the methyl radical were first examined by Yu et al, 11 and it was found that the 3s Rydberg state (B 2 A 1 Ј) is correlated to the singlet methylene, CH 2 (ã 1 A 1 ) with a small barrier ͑about 9 kcal/ mol͒ and the ground state methyl radical is correlated to two asymptotic dissociation channels, CH 2 (X 3 B 1 )ϩH( 2 S) and CH(X 2 ⌸)ϩH 2 ( 1 ⌺ g ϩ ). It is therefore interesting to know whether ground state dissociation plays any significant role in this case.…”

Section: Introductionmentioning
confidence: 99%

Photodissociation dynamics of the methyl radical at 212.5 nm: Effect of parent internal excitation
Wu
¹
,
Jiang
²
,
Qin
³

et al. 2004
The Journal of Chemical Physics
27
4
18
0
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Photodissociation dynamics of the CH 3 radical at 212.5 nm has been investigated using the H atom Rydberg tagging time-of-flight method with a pure CH 3 radical source generated by the photolysis of CH 3 I at 266 nm. Time-of-flight spectra of the H atom products from the photolysis of both cold and hot methyl radicals have been measured at different photolysis polarizations. Experimental results indicate that the photodissociation of the methyl radical in its ground vibrational state at 212.5 nm excitation occurs on a very fast time scale in comparison with its rotational period, indicating the CH 3 dissociation at 212.5 nm occurs on the excited 3s Rydberg state surface. Experimental evidence also shows that the photodissociation of the methyl radical in the 2 ϭ1 state of the umbrella mode at 212.5 nm excitation is characteristically different from that in the ground vibrational state.

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“…It is well established that the ground electronic state of CH 3 is of D3h planar symmetry with an electron configuration, (31) It has generally been known that spin-conservation rule holds in energy-transfer reactions from Rgep 2 ) to simple molecules. 1 .4 According to the spin-conservation rule, precursor CHf leading to CH(A,B) must be doublet.…”

Section: B Rovibrational Distributions Of Ch(ab)mentioning
confidence: 99%

Rovibrational distributions of CH(A 2Δ,B 2Σ−) produced in energy-transfer reactions from Ar(3P2), Kr(3P2), and Xe(3P2) atoms to CH3 radical
Tsuji
¹
,
Kouno
²
,
Nishimura
³

et al. 1991
The Journal of Chemical Physics
7
0
0
0
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Articles you may be interested inVibrational distributions of KrF(B) and XeCl(B) produced from ionicrecombination reactions of Kr+(2 P 3/2)+SF− 6 and Xe+(2 P 3/2)+Cl−+He Rovibrational distributions of CH(A 2Δ) produced in energytransfer reactions from Ar(3 P 2), Kr(3 P 2), and Xe(3 P 2) atoms to C2H5 radical Energy-transfer reactions from ArCP 2 ), KrCP 2 ), and XeCP 2 ) to CH 3 radical have been studied by observing emission spectra from excited fragments in the flowing afterglow. CH 3 radicals were generated by the F + CH 4 reaction. The CH(A 2a-X2IIr:v' = 0 -2) and CH(B 2~ --X 2 II r :v' = 0) emission systems were observed in the ArCP 2 ) reaction, while only CH(A-X:v' = 0,1) emission system was found in the KrCP 2 ) and XeCP 2 ) reactions. The nascent rovibrational distributions of CH(A:v' = 0-2) were No :N 1 :N 2 = l00( To = 3400 ± 400 K):28 ± 5(T 1 = 1700 ± 400 K):4 ± l(T 2 = 700 ± 300 K) in the ArCP 2 ) reaction and l00( To' = 1000 ± 250 K): < 5 (T 1 < 800 K):O in the Kr( 3 P 2 ) and Xe ( 3 P2 ) reactions. The rotational distribution of CH(B:v' = 0) in the ArCP 2 ) reaction was reproduced by a single Boltzmann temperature of 2800 ± 300 K. The average fractions of total available energies channeled into vibration and rotation ofCH (A,B) were less than 15% for all cases, suggesting that most of the available energies was deposited as relative translational energy of products and/or rovibrational energy ofH 2 • The observed rovibrational distributions of CH (A) were colder than those predicted from statistical theories including and excluding the conservation of total angular momentum. The best agreement between the observed and statistical distributions was obtained for the mechanism giving CH(A,B) in two-body dissociation steps by assuming that 78-92% of the total available energy is released as kinetic energy in the first step, Rgep 2 ) + CH 3 --CHt + Rg, then the rest remains in the precursor CHr state as an internal energy. CH 4 , CF 4 , and Ar in the discharge tube were 0.01-0.015, J. Chern. Phys. 95 (10),

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Erratum: A comparative theoretical analysis of the photochemistry of the methyl radical and related systems [J. Chem. Phys. 8 , 2049 (1984)]

Cited by 13 publications

References 0 publications

Photodissociation dynamics of the methyl radical 3s Rydberg state

Photodissociation dynamics of the methyl radical 3s Rydberg state

Photodissociation dynamics of the methyl radical at 212.5 nm: Effect of parent internal excitation

Rovibrational distributions of CH(A 2Δ,B 2Σ−) produced in energy-transfer reactions from Ar(3P2), Kr(3P2), and Xe(3P2) atoms to CH3 radical

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