PMID- 18459757
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20080807
LR  - 20080529
IS  - 1520-5215 (Electronic)
IS  - 1089-5639 (Linking)
VI  - 112
IP  - 22
DP  - 2008 Jun 5
TI  - Infrared spectroscopy of gas phase benzenium ions: protonated benzene and 
      protonated toluene, from 750 to 3400 cm-1.
PG  - 4869-74
LID - 10.1021/jp802020n [doi]
AB  - Gas phase C 6H 7 (+) and C 7H 9 (+) ions are studied with infrared 
      photodissociation spectroscopy (IRPD) and the method of rare gas tagging. The 
      ions are produced in a pulsed electric discharge supersonic expansion source from 
      benzene or toluene precursors. We observe exclusively the formation of either the 
      C 2 v benzenium ion (protonated benzene) or the para isomer of the toluenium ion 
      (protonated toluene). The infrared spectral signatures associated with each ion 
      are established between 750 and 3400 cm (-1). Comparing the gas phase spectrum of 
      the benzenium ion to the spectrum obtained in a superacid matrix [ Perkampus, H. 
      H.; Baumgarten, E. Angew. Chem. Int. Ed. 1964, 3, 776 ], we find that the C 2 v 
      structure of the gas phase species is minimally affected by the matrix 
      environment. An intense band near 1610 cm (-1) is observed for both ions and is 
      indicative of the allylic pi-electron density associated with the six membered 
      ring in these systems. This spectral signature, also observed for alkyl 
      substituted benzenium ions and protonated naphthalene, compares favorably with 
      the interstellar, unidentified infrared emission band near 6.2 microm (1613 cm 
      (-1)).
FAU - Douberly, G E
AU  - Douberly GE
FAU - Ricks, A M
AU  - Ricks AM
FAU - Schleyer, P v R
AU  - Schleyer Pv
FAU - Duncan, M A
AU  - Duncan MA
LA  - eng
PT  - Letter
DEP - 20080507
PL  - United States
TA  - J Phys Chem A
JT  - The journal of physical chemistry. A
JID - 9890903
EDAT- 2008/05/08 09:00
MHDA- 2008/05/08 09:01
CRDT- 2008/05/08 09:00
PHST- 2008/05/08 09:00 [pubmed]
PHST- 2008/05/08 09:01 [medline]
PHST- 2008/05/08 09:00 [entrez]
AID - 10.1021/jp802020n [doi]
PST - ppublish
SO  - J Phys Chem A. 2008 Jun 5;112(22):4869-74. doi: 10.1021/jp802020n. Epub 2008 May 
      7.