Pregled bibliografske jedinice broj: 997321
Phenyl radical, cation, and anion. The triplet- singlet gap and higher excited states of the phenyl cation
Phenyl radical, cation, and anion. The triplet- singlet gap and higher excited states of the phenyl cation // Journal of the American Chemical Society, 119 (1997), 34; 8083-8088 doi:10.1021/ja970808s (međunarodna recenzija, članak, znanstveni)
CROSBI ID: 997321 Za ispravke kontaktirajte CROSBI podršku putem web obrasca
Naslov
Phenyl radical, cation, and anion. The triplet-
singlet gap and higher excited states of the
phenyl cation
Autori
Nicolaides, Athanassios ; Smith, David M. ; Jensen, Frank ; Radom, Leo
Izvornik
Journal of the American Chemical Society (0002-7863) 119
(1997), 34;
8083-8088
Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni
Ključne riječi
Phenyl radical ; Phenyl cation ; Phenyl anion ; triplet-singlet gap
Sažetak
High-level ab initio molecular orbital calculations have been carried out for the phenyl cation (1), the phenyl radical (2), and the phenyl anion (3). Our best estimate for the heat of formation (Delta H-f298) Of the phenyl radical is 340 kJ mol(-1), corresponding to 476 kJ mol(-1) for the 298 K C-H bond dissociation energy in benzene. The calculated Delta H-f298 Of the phenyl anion is 224 kJ mol(-1), leading to an electron affinity for the phenyl radical of 116 kJ mol(-1), and a gas-phase acidity for benzene of 1671 kJ mol(-1). The ground state of the phenyl cation is found to be a singlet (1-(1)A(1), Delta H-f298 = 1134 kJ mol(-1)), with the tripler (1-B-3(1), Delta H-f298 = 1237 kJ mol(-1)) lying significantly higher in energy (by 103 kJ mol(-1)). The energies of the 1-(1)A(1) and 1-B- 3(1) states of the phenyl cation at the phenyl radical geometry are much closer, but 1-(1)A(1) remains the energetically lowest electronic state. The essentially isoenergetic 1-(3)A(2) and 1- (1)A(2) states lie about 25 kJ mol(-1) higher in energy than 1-B-3(1), while 1-B-1(1) is nearly 60 kJ mol(-1) higher in energy. The implications of these results with respect to recent spectroscopic studies of the phenyl radical and the role of the triplet phenyl cation in the dissociation of benzene cation are discussed.
Izvorni jezik
Engleski
Znanstvena područja
Kemija
Citiraj ovu publikaciju:
Časopis indeksira:
- Web of Science Core Collection (WoSCC)
- Science Citation Index Expanded (SCI-EXP)
- SCI-EXP, SSCI i/ili A&HCI
- Scopus