Benzene, hexamethyl-
- Formula: C12H18
- Molecular weight: 162.2713
- IUPAC Standard InChIKey: YUWFEBAXEOLKSG-UHFFFAOYSA-N
- CAS Registry Number: 87-85-4
- 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. - Isotopologues:
- Other names: Hexamethylbenzene; Mellitene; 1,2,3,4,5,6-Hexamethylbenzene
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Gas phase ion energetics data
Go To: Top, Ion clustering data, Mass spectrum (electron ionization), 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:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess
View reactions leading to C12H18+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 7.85 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 205.7 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 199.8 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
EA (eV) | Method | Reference | Comment |
---|---|---|---|
<0.121 ± 0.017 | ECD | Wojnarovits and Foldiak, 1981 | EA is an upper limit: Chen and Wentworth, 1989. G3MP2B3 calculations indicate an EA of ca. -0.1 eV, anion unbound.; B |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
7.85 | PE | Howell, Goncalves, et al., 1984 | LBLHLM |
7.87 | EI | Kuznesof, Stafford, et al., 1967 | RDSH |
7.85 ± 0.02 | PI | Vilesov, 1961 | RDSH |
7.85 | PI | Bralsford, Harris, et al., 1960 | RDSH |
7.8 | CTS | Foster, 1959 | RDSH |
7.95 | CTS | Briegleb and Czekalla, 1959 | RDSH |
7.85 | PE | Howell, Goncalves, et al., 1984 | Vertical value; LBLHLM |
7.9 | PE | Kovac, Mohraz, et al., 1980 | Vertical value; LLK |
Ion clustering data
Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Michael M. Meot-Ner (Mautner) and Sharon G. Lias
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
By formula: C6H7N+ + C12H18 = (C6H7N+ • C12H18)
Bond type: Charge transfer bond (positive ion)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 17.1 | kcal/mol | PHPMS | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase |
Quantity | Value | Units | Method | Reference | Comment |
ΔrS° | 24.3 | cal/mol*K | PHPMS | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase |
Mass spectrum (electron ionization)
Go To: Top, Gas phase ion energetics data, Ion clustering data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Spectrum
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Additional Data
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
Origin | Japan AIST/NIMC Database- Spectrum MS-NW- 223 |
NIST MS number | 228195 |
References
Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), 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]
Howell, Goncalves, et al., 1984
Howell, J.O.; Goncalves, J.M.; Amatore, C.; Klasinc, L.; Wightman, R.M.; Kochi, J.K.,
Electron transfer from aromatic hydrocarbons and their π-complexes with metals. Comparison of the standard oxidation potentials and vertical ionization potentials,
J. Am. Chem. Soc., 1984, 106, 3968. [all data]
Kuznesof, Stafford, et al., 1967
Kuznesof, P.M.; Stafford, F.E.; Shriver, D.F.,
Electron impact ionization potentials of methyl-substituted borazines,
J. Phys. Chem., 1967, 71, 1939. [all data]
Vilesov, 1961
Vilesov, F.I.,
Photoionisation of organic vapours in the vacuum ultra-violet,
Zh. Fiz. Khim., 1961, 35, 2010, In original 986. [all data]
Bralsford, Harris, et al., 1960
Bralsford, R.; Harris, P.V.; Price, W.C.,
The effect of fluorine on the electronic spectra and ionization potentials of molecules,
Proc. Roy. Soc. (London), 1960, A258, 459. [all data]
Foster, 1959
Foster, R.,
Ionization potentials of electron donors,
Nature (London), 1959, 183, 1253. [all data]
Briegleb and Czekalla, 1959
Briegleb, G.; Czekalla, J.,
Die Bestimmung von lonisierungsenergien aus den Spektren von Elektronenubergangskomplexen,
Z.Elektrochem., 1959, 63, 6. [all data]
Kovac, Mohraz, et al., 1980
Kovac, B.; Mohraz, M.; Heilbronner, E.; Boekelheide, V.; Hopf, H.,
Photoelectron spectra of the cyclophanes,
J. Am. Chem. Soc., 1980, 102, 4314. [all data]
Meot-Ner (Mautner) and El-Shall, 1986
Meot-Ner (Mautner), M.; El-Shall, M.S.,
Ionic Charge Transfer Complexes. 1. Cationic Complexes with Delocalized and Partially Localized pi Systems,
J. Am. Chem. Soc., 1986, 108, 15, 4386, https://doi.org/10.1021/ja00275a026
. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References
- Symbols used in this document:
EA Electron affinity IE (evaluated) Recommended ionization energy ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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