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, Gas Chromatography, 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) | 860.6 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 836.0 | kJ/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 |
Gas Chromatography
Go To: Top, Gas phase ion energetics 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
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Capillary | HP-5 | 120. | 1452.4 | Pérez-Parajón, Santiuste, et al., 2004 | 60. m/0.25 mm/0.25 μm |
Capillary | OV-101 | 100. | 1416. | Gerasimenko and Nabivach, 1982 | N2; Column length: 50. m; Column diameter: 0.30 mm |
Capillary | OV-101 | 120. | 1428. | Gerasimenko and Nabivach, 1982 | N2; Column length: 50. m; Column diameter: 0.30 mm |
Capillary | OV-101 | 140. | 1442. | Gerasimenko and Nabivach, 1982 | N2; Column length: 50. m; Column diameter: 0.30 mm |
Capillary | OV-101 | 100. | 1415.6 | Gerasimenko, Kirilenko, et al., 1981 | N2; Column length: 50. m; Column diameter: 0.3 mm |
Capillary | OV-101 | 120. | 1428.2 | Gerasimenko, Kirilenko, et al., 1981 | N2; Column length: 50. m; Column diameter: 0.3 mm |
Capillary | OV-101 | 140. | 1441.6 | Gerasimenko, Kirilenko, et al., 1981 | N2; Column length: 50. m; Column diameter: 0.3 mm |
Capillary | Squalane | 100. | 1415. | Engewald and Wennrich, 1976 | N2; Column length: 100. m; Column diameter: 0.23 mm |
Kovats' RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | OV-101 | 1431. | Hayes and Pitzer, 1982 | 110. m/0.25 mm/0.20 μm, He, 1. K/min; Tstart: 35. C; Tend: 200. C |
Kovats' RI, polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Capillary | Carbowax 20M | 100. | 1778.0 | Engewald and Wennrich, 1976 | N2; Column length: 100. m; Column diameter: 0.23 mm |
Van Den Dool and Kratz RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Petrocol DH | 1437. | White, Hackett, et al., 1992 | 100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C |
Capillary | OV-101 | 1431. | Hayes and Pitzer, 1981 | 108. m/0.25 mm/0.2 μm, 1. K/min; Tstart: 35. C; Tend: 200. C |
Normal alkane RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Petrocol DH | 1437. | Supelco, 2012 | 100. m/0.25 mm/0.50 μm, Helium, 20. C @ 15. min, 15. K/min, 220. C @ 30. min |
Normal alkane RI, non-polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | OV-1, SE-30, Methyl silicone, SP-2100, OV-101, DB-1, etc. | 1431. | Waggott and Davies, 1984 | Hydrogen; Column length: 50. m; Column diameter: 0.32 mm; Program: not specified |
References
Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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]
Pérez-Parajón, Santiuste, et al., 2004
Pérez-Parajón, J.M.; Santiuste, J.M.; Takács, J.M.,
Sensitivity of the methylbenzenes and chlorobenzenes retention index to column temperature, stationary phase polarity, and number and chemical nature of substituents,
J. Chromatogr. A, 2004, 1048, 2, 223-232, https://doi.org/10.1016/j.chroma.2004.07.028
. [all data]
Gerasimenko and Nabivach, 1982
Gerasimenko, V.A.; Nabivach, V.M.,
Relationship between molecular structure and gas chromatographic retention of alkylbenzenes C8-C1 2 on polydimethylsiloxane,
Zh. Anal. Khim., 1982, 37, 110-116. [all data]
Gerasimenko, Kirilenko, et al., 1981
Gerasimenko, V.A.; Kirilenko, A.V.; Nabivach, V.M.,
Capillary gas chromatography of aromatic compounds found in coal tar fractions,
J. Chromatogr., 1981, 208, 1, 9-16, https://doi.org/10.1016/S0021-9673(00)87953-4
. [all data]
Engewald and Wennrich, 1976
Engewald, W.; Wennrich, L.,
Molekülstruktur und Retentionsverhalten. VIII. Zum Retentionsverhalten höherer Alkylbenzole bei der Gas-Verteilungs-Chromatographie,
Chromatographia, 1976, 9, 11, 540-547, https://doi.org/10.1007/BF02275960
. [all data]
Hayes and Pitzer, 1982
Hayes, P.C., Jr.; Pitzer, E.W.,
Characterizing petroleum- and shale-derived jet fuel distillates via temperature-programmed Kováts indices,
J. Chromatogr., 1982, 253, 179-198, https://doi.org/10.1016/S0021-9673(01)88376-X
. [all data]
White, Hackett, et al., 1992
White, C.M.; Hackett, J.; Anderson, R.R.; Kail, S.; Spock, P.S.,
Linear temperature programmed retention indices of gasoline range hydrocarbons and chlorinated hydrocarbons on cross-linked polydimethylsiloxane,
J. Hi. Res. Chromatogr., 1992, 15, 2, 105-120, https://doi.org/10.1002/jhrc.1240150211
. [all data]
Hayes and Pitzer, 1981
Hayes, P.C., Jr.; Pitzer, E.W.,
Kovats indices as a tool in characterizing hydrocarbon fuels in temperature programmed glass capillary gas chromatography. Part 1. Qualitative identification, Inhouse rpt. for Air Force Wright Aeronautical Labs., Air Force Wright Aeronautical Labs., Wright-Patterson AFB, Ohio, 1981, 75. [all data]
Supelco, 2012
Supelco, CatalogNo. 24160-U,
Petrocol DH Columns. Catalog No. 24160-U, 2012, retrieved from http://www.sigmaaldrich.com/etc/medialib/docs/Supelco/Datasheet/1/w97949.Par.0001.File.tmp/w97949.pdf. [all data]
Waggott and Davies, 1984
Waggott, A.; Davies, I.W.,
Identification of organic pollutants using linear temperature programmed retention indices (LTPRIs) - Part II, 1984, retrieved from http://dwi.defra.gov.uk/research/completed-research/reports/dwi0383.pdf. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Gas Chromatography, References
- Symbols used in this document:
EA Electron affinity IE (evaluated) Recommended ionization energy - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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