Indene
- Formula: C9H8
- Molecular weight: 116.1598
- IUPAC Standard InChIKey: YBYIRNPNPLQARY-UHFFFAOYSA-N
- CAS Registry Number: 95-13-6
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript. - Other names: 1H-Indene
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Gas phase ion energetics data
Go To: Top, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
MM - Michael M. Meot-Ner (Mautner)
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C9H8+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 8.14 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 202.9 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 195.9 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
<0.173 ± 0.026 | ECD | Wojnarovits and Foldiak, 1981 | EA is an upper limit: Chen and Wentworth, 1989; G3MP2B3 calculations indicate an EA of ca. -0.6 eV, unbound anion.; B |
Proton affinity at 298K
Proton affinity (kcal/mol) | Reference | Comment |
---|---|---|
202.8 | Aue, Guidoni, et al., 2000 | Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM |
Gas basicity at 298K
Gas basicity (review) (kcal/mol) | Reference | Comment |
---|---|---|
195.8 | Aue, Guidoni, et al., 2000 | Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.33 ± 0.01 | EI | Rakita, Hoffman, et al., 1973 | LLK |
8.14 ± 0.01 | PE | Dewar, Haselbach, et al., 1970 | RDSH |
8.62 | EI | Occolowitz and White, 1968 | RDSH |
8.13 ± 0.05 | PE | Eland and Danby, 1968 | RDSH |
8.15 ± 0.015 | PE | Gusten, Klasinc, et al., 1976 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C9H7+ | 12.62 ± 0.05 | H | EI | Schwarz and Bohlmann, 1973 | LLK |
C9H7+ | 12.53 | H | EI | Occolowitz and White, 1968 | RDSH |
De-protonation reactions
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 354.3 ± 2.5 | kcal/mol | TDEq | Meot-ner, Liebman, et al., 1988 | gas phase; anchored to 88MEO scale, not the "87 acidity scale". The Kiefer, Zhang, et al., 1997 BDE is for ortho.; B |
ΔrH° | 351.9 ± 2.1 | kcal/mol | G+TS | Taft and Bordwell, 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 346.7 ± 2.0 | kcal/mol | TDEq | Meot-ner, Liebman, et al., 1988 | gas phase; anchored to 88MEO scale, not the "87 acidity scale". The Kiefer, Zhang, et al., 1997 BDE is for ortho.; B |
ΔrG° | 344.6 ± 2.0 | kcal/mol | IMRE | Taft and Bordwell, 1988 | gas phase; B |
References
Go To: Top, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G.,
Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update,
J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018
. [all data]
Wojnarovits and Foldiak, 1981
Wojnarovits, L.; Foldiak, G.,
Electron capture detection of aromatic hydrocarbons,
J. Chromatogr. Sci., 1981, 206, 511. [all data]
Chen and Wentworth, 1989
Chen, E.C.M.; Wentworth, W.E.,
Experimental Determination of Electron Affinities of Organic Molecules,
Mol. Cryst. Liq. Cryst., 1989, 171, 271. [all data]
Aue, Guidoni, et al., 2000
Aue, D.H.; Guidoni, M.; Betowski, L.D.,
Ab initio calculated gas-phase basicities of polynuclear aromatic hydrocarbons,
Int. J. Mass Spectrom., 2000, 201, 283. [all data]
Rakita, Hoffman, et al., 1973
Rakita, P.E.; Hoffman, M.K.; Andrews, M.N.; Bursey, M.M.,
σ-π Conjugation in group IVA compounds of indene and indane,
J. Organomet. Chem., 1973, 49, 213. [all data]
Dewar, Haselbach, et al., 1970
Dewar, M.J.S.; Haselbach, E.; Worley, S.D.,
Calculated and observed ionization potentials of unsaturated polycyclic hydrocarbons; calculated heats of formation by several semiempirical s.c.f. m.o. methods,
Proc. Roy. Soc. (London), 1970, A315, 431. [all data]
Occolowitz and White, 1968
Occolowitz, J.L.; White, G.L.,
Energetic considerations in the assignment of some fragment ion structures,
Australian J. Chem., 1968, 21, 997. [all data]
Eland and Danby, 1968
Eland, J.H.D.; Danby, C.J.,
Inner ionization potentials of aromatic compounds,
Z. Naturforsch., 1968, 23a, 355. [all data]
Gusten, Klasinc, et al., 1976
Gusten, H.; Klasinc, L.; Ruscic, B.,
Photoelectron spectroscopy of J. Heterocycl. Chem.. Indene analogs,
Z. Naturforsch. A:, 1976, 31, 1051. [all data]
Schwarz and Bohlmann, 1973
Schwarz, H.; Bohlmann, F.,
Elektronenstossinduzierte fragmentierung von acetylenverbindungen. VI. Struktur und bildungsenthalpie der ionen [C11H9]+ und [C9H7]+,
Org. Mass Spectrom., 1973, 7, 395. [all data]
Meot-ner, Liebman, et al., 1988
Meot-ner, M.; Liebman, J.F.; Kafafi, S.A.,
Ionic Probes of Aromaticity in Annelated Rings,
J. Am. Chem. Soc., 1988, 110, 18, 5937, https://doi.org/10.1021/ja00226a001
. [all data]
Kiefer, Zhang, et al., 1997
Kiefer, J.H.; Zhang, Q.; Kern, R.D.; Yao, J.; Jursic, B.,
Pyrolysis of Aromatic Azines: Pyrazine, Pyrimidine, and Pyridine,
J. Phys. Chem. A, 1997, 101, 38, 7061, https://doi.org/10.1021/jp970211z
. [all data]
Taft and Bordwell, 1988
Taft, R.W.; Bordwell, F.G.,
Structural and Solvent Effects Evaluated from Acidities Measured in Dimethyl Sulfoxide and in the Gas Phase,
Acc. Chem. Res., 1988, 21, 12, 463, https://doi.org/10.1021/ar00156a005
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity IE (evaluated) Recommended ionization energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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