Electron spin resonance of monomer and dimer cations of 1,4-, 1,5- and 1,8-dimethylnaphthalenes

Yoshimi, H.; Kuwata, Keiji

doi:10.1080/00268977200100301

Cited by 21 publications

(4 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar hfcc reduction has been reported for the methyl protons of the dimer cations of aromatics such as toluene 11 and dimethylnaphthalenes. 13 Yoshimi et al 13 succeeded in reproducing the hf reduction using a simple Hu ¨ckel MO method. It is of interest to observe how the hfcc reduction can be reproduced by the more advanced MO method.…”

Section: Optimized Structure and 19 F-hfccmentioning

confidence: 99%

“…Recently, one of the present authors succeeded in observing an anisotropic 1 H-hfcc of the ring protons of the (C 6 H 6 ) 2 + using the ENDOR method which enabled us to evaluate the intra-molecular distance more precisely. 11,12 In the case of methyl-substituted aromatic compounds such as toluene 11,12 and methylnaphthalene, 13 the 1 H-hfcc of the methyl protons of the associated dimmer cation became smaller than half that of the monomeric cations, which may be caused by interaction between the two benzene rings.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Formation and structure of dimer radical cations of fluorinated benzenes in solid matrices

Itagaki

Yanagida

Shiotani

2002

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Structures of dimeric radical cations of fluorinated benzenes (C 6 H 5 F + and 1,4-C 6 H 4 F 2 + ) formed by girradiation in solid halocarbon matrices were investigated by means of EPR and DFT calculations. For both the dimer cations, sandwich type structures, where the two benzene rings are symmetrically overlapped, were suggested, and the 19 F-hyperfine coupling constants of the dimeric cations were found to be smaller than half that of the corresponding monomer cations. This was qualitatively explained in terms of the anti-bonding feature of the C-C bond between the two benzene rings and the C-F bond. DFT calculations performed for the monomer and dimer cations successfully account for this phenomenon. Anisotropic 19 F hyperfine coupling (b) was used as a good indicator for evaluating the distance between the two benzene rings. The formation of the dimer cations strongly depends on the matrices and the concentration of the solutes, suggesting that molecular diffusion in the solid systems is an important factor in the dimerization.

show abstract

Section: Optimized Structure and 19 F-hfccmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Formation and structure of dimer radical cations of fluorinated benzenes in solid matrices

Itagaki

Yanagida

Shiotani

2002

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…Radical cations, i.e., one-electron oxidation products of the following compounds, were studied; less common radical cations are shown in Table IV: amines (117,202,203), substituted benzenes (39,41,(161)(162)(163)164), substituted biphenyls (91,174), substituted naphthalenes (64,195), substituted 4,4'-bipyridyls (144), rubrene (20), and a variety of heterocyclic azines (74).…”

Section: Use Of Esr In Determination Of Transition Metal Ions Water A...mentioning

confidence: 99%

Electron spin resonance

Janzen¹

1974

Anal. Chem.

View full text Add to dashboard Cite

Born in Manitoba, Canada, he received his BSc and MSc degrees in chemistry at the University of Manitoba in 1957 and 1960 and his PhD degree from Iowa State University in 1963. He joined the chemistry staff at the University of Georgia in 1964 as assistant professor (1964-68) after spending seven months on a postdoctoral appointment at Iowa State University. His research interests are in the area of electron spin resonance applications to studies of the structure and mechani sms of free radicals.

show abstract

“…A well-established reaction of olefin radical cations is dimerization with a neutral parent molecule to form a dimer cation. [3][4][5][6] Dimer cations of olefins were first observed by optical methods in low temperature glasses.3 Several years later EPR experiments in low temperature glasses confirmed olefin dimer cation formation.4 About the same time, kinetic data for the dimerization of several olefins were estimated by optical methods.5,6 More recently, optically detected EPR spectral lines observed in fluid solution have been attributed to the presence of olefin dimer cations. 6 We have utilized time-resolved fluorescence detected magnetic resonance (FDMR), developed in our laboratory,7 to undertake a detailed study of olefin dimer cation formation.…”

Section: Introductionmentioning

confidence: 99%

Structure and dynamics of olefin radical cation aggregates. Time-resolved fluorescence detected magnetic resonance

Desrosiers¹,

Trifunac²

1986

J. Phys. Chem.

View full text Add to dashboard Cite

The time-resolved EPR spectra and thus the structure and dynamics of transient hydrocarbon radical cations are obtained by the pulse radiolysis-fluorescence detected magnetic resonance (FDMR) technique. Here we report the observation of short-lived radical cations from olefins. FDMR-EPR spectra of radical cations from tetramethylethylene and cyclohexadiene are illustrated. The olefin radical cations' FDMR spectra are concentration-dependent, since dimerization with neutral molecules takes place at higher (>lo-* M) olefin concentration. Rate constants for the dimerization reaction are derived and the effect of solvent viscosity on aggregate formation is demonstrated. By monitoring the further reactions of dimer cations, we have obtained EPR evidence for previously unobserved higher-order (multimer) radical cation aggregates of olefins.

show abstract

Electron spin resonance of monomer and dimer cations of 1,4-, 1,5- and 1,8-dimethylnaphthalenes

Cited by 21 publications

References 19 publications

Formation and structure of dimer radical cations of fluorinated benzenes in solid matrices

Formation and structure of dimer radical cations of fluorinated benzenes in solid matrices

Electron spin resonance

Structure and dynamics of olefin radical cation aggregates. Time-resolved fluorescence detected magnetic resonance

Contact Info

Product

Resources

About