Benzene, hexamethyl-

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.


Gas phase thermochemistry data

Go To: Top, Phase change data, Mass spectrum (electron ionization), 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 compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas-77.4 ± 2.5kJ/molCcbColomina, Jimenez, et al., 1989see Boned, Colomina, et al., 1964; ALS
Δfgas-78.3kJ/molN/AParks, West, et al., 1946Value computed using ΔfHsolid° value of -163.3±3.1 kj/mol from Parks, West, et al., 1946 and ΔsubH° value of 85.0 kj/mol from Parks, West, et al., 1946.; DRB

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
184.4200.Draeger, 1985Recommended values are in close agreement with experimental data on S(T). Discrepancies with earlier statistically calculated values [ Hastings S.H., 1957] amount to 16 and 13 J/mol*K in S(T) and Cp(T), respectively.; GT
227.3273.15
241.5 ± 0.4298.15
242.6300.
298.3400.
349.3500.
393.8600.
432.1700.
465.0800.
493.4900.
517.91000.
539.01100.
557.31200.
573.11300.
586.71400.
598.61500.

Phase change data

Go To: Top, Gas phase thermochemistry data, Mass spectrum (electron ionization), 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 compiled as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil538.2KN/AWeast and Grasselli, 1989BS
Tboil536.85KN/ACooper, Crowne, et al., 1967Uncertainty assigned by TRC = 0.6 K; TRC
Quantity Value Units Method Reference Comment
Tfus438. ± 3.KAVGN/AAverage of 13 values; Individual data points
Quantity Value Units Method Reference Comment
Tc758. ± 1.KN/ATsonopoulos and Ambrose, 1995 
Tc758.KN/AAmbrose, Broderick, et al., 1974Uncertainty assigned by TRC = 2. K; TRC
Tc751.15KN/AGuye and Mallet, 1902Uncertainty assigned by TRC = 10. K; crit. temp. greater than this - sample decomposes at this T; TRC
Quantity Value Units Method Reference Comment
Δvap68.6kJ/molCGCZhao, Unhannanant, et al., 2008AC
Quantity Value Units Method Reference Comment
Δsub83. ± 7.kJ/molAVGN/AAverage of 7 values; Individual data points

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
56.8458.AStephenson and Malanowski, 1987Based on data from 443. to 537. K.; AC

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
85.2320.AAmbrose, Lawrenson, et al., 1976Based on data from 303. to 338. K.; AC
83.2329.AOverberger, Steele, et al., 1969Based on data from 314. to 364. K.; AC

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
20.63438.7Domalski and Hearing, 1996See also Spaght, Thomas, et al., 1931.; AC

Entropy of fusion

ΔfusS (J/mol*K) Temperature (K) Reference Comment
4.58383.7Domalski and Hearing, 1996CAL
47.02438.7

Temperature of phase transition

Ttrs (K) Initial Phase Final Phase Reference Comment
382.crystaline, IIIcrystaline, IFujiwara, Inaba, et al., 1992DH
439.crystaline, IliquidFujiwara, Inaba, et al., 1992DH

Enthalpy of phase transition

ΔHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
1.100117.5crystaline, IIIcrystaline, IIFujiwara, Inaba, et al., 1992From Atake, Gyoten, et al., 1982; DH
1.500384.0crystaline, IIcrystaline, IPetropavlov, Tsygankova, et al., 1988DH
1.103115.5crystaline, IIcrystaline, IYoshimoto, Fujiwara, et al., 1985DH
0.990117.5crystaline, IIIcrystaline, IIAtake, Gyoten, et al., 1982First order transition.; DH
1.1284116.48crystaline, IIcrystaline, IFrankosky and Aston, 1965Entropy obtained as difference of integral of observed Cp over range 115 to 128 K, and integral of extrapolated Cp data.; DH
1.841383.55crystaline, IIcrystaline, IMomotani, Suga, et al., 1956DH
20.585438.35crystaline, IliquidMomotani, Suga, et al., 1956DH
1.766383.7crystaline, IIcrystaline, ISpaght, Thomas, et al., 1932DH
20.640438.7crystaline, IliquidSpaght, Thomas, et al., 1932DH
1.017108.crystaline, IIIcrystaline, IIHuffman, Parks, et al., 1930DH
0.155151.crystaline, IIcrystaline, IHuffman, Parks, et al., 1930DH

Entropy of phase transition

ΔStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
9.3117.5crystaline, IIIcrystaline, IIFujiwara, Inaba, et al., 1992From; DH
3.9384.0crystaline, IIcrystaline, IPetropavlov, Tsygankova, et al., 1988DH
9.55115.5crystaline, IIcrystaline, IYoshimoto, Fujiwara, et al., 1985DH
8.3117.5crystaline, IIIcrystaline, IIAtake, Gyoten, et al., 1982First; DH
10.08116.48crystaline, IIcrystaline, IFrankosky and Aston, 1965Entropy; DH
4.81383.55crystaline, IIcrystaline, IMomotani, Suga, et al., 1956DH
46.86438.35crystaline, IliquidMomotani, Suga, et al., 1956DH
4.60383.7crystaline, IIcrystaline, ISpaght, Thomas, et al., 1932DH
47.0438.7crystaline, IliquidSpaght, Thomas, et al., 1932DH
9.5108.crystaline, IIIcrystaline, IIHuffman, Parks, et al., 1930DH
1.0151.crystaline, IIcrystaline, IHuffman, Parks, et al., 1930DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Phase change data, 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 compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

Mass spectrum
For Zoom
1.) Enter the desired X axis range (e.g., 100, 200)
2.) Check here for automatic Y scaling
3.) Press here to zoom

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

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


Gas Chromatography

Go To: Top, Gas phase thermochemistry data, Phase change 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

View large format table.

Column type Active phase Temperature (C) I Reference Comment
CapillaryHP-5120.1452.4Pérez-Parajón, Santiuste, et al., 200460. m/0.25 mm/0.25 μm
CapillaryOV-101100.1416.Gerasimenko and Nabivach, 1982N2; Column length: 50. m; Column diameter: 0.30 mm
CapillaryOV-101120.1428.Gerasimenko and Nabivach, 1982N2; Column length: 50. m; Column diameter: 0.30 mm
CapillaryOV-101140.1442.Gerasimenko and Nabivach, 1982N2; Column length: 50. m; Column diameter: 0.30 mm
CapillaryOV-101100.1415.6Gerasimenko, Kirilenko, et al., 1981N2; Column length: 50. m; Column diameter: 0.3 mm
CapillaryOV-101120.1428.2Gerasimenko, Kirilenko, et al., 1981N2; Column length: 50. m; Column diameter: 0.3 mm
CapillaryOV-101140.1441.6Gerasimenko, Kirilenko, et al., 1981N2; Column length: 50. m; Column diameter: 0.3 mm
CapillarySqualane100.1415.Engewald and Wennrich, 1976N2; Column length: 100. m; Column diameter: 0.23 mm

Kovats' RI, non-polar column, temperature ramp

View large format table.

Column type Active phase I Reference Comment
CapillaryOV-1011431.Hayes and Pitzer, 1982110. m/0.25 mm/0.20 μm, He, 1. K/min; Tstart: 35. C; Tend: 200. C

Kovats' RI, polar column, isothermal

View large format table.

Column type Active phase Temperature (C) I Reference Comment
CapillaryCarbowax 20M100.1778.0Engewald and Wennrich, 1976N2; Column length: 100. m; Column diameter: 0.23 mm

Van Den Dool and Kratz RI, non-polar column, temperature ramp

View large format table.

Column type Active phase I Reference Comment
CapillaryPetrocol DH1437.White, Hackett, et al., 1992100. m/0.25 mm/0.5 μm, He, 1. K/min; Tstart: 30. C; Tend: 220. C
CapillaryOV-1011431.Hayes and Pitzer, 1981108. m/0.25 mm/0.2 μm, 1. K/min; Tstart: 35. C; Tend: 200. C

Normal alkane RI, non-polar column, temperature ramp

View large format table.

Column type Active phase I Reference Comment
CapillaryPetrocol DH1437.Supelco, 2012100. 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

View large format table.

Column type Active phase I Reference Comment
CapillaryOV-1, SE-30, Methyl silicone, SP-2100, OV-101, DB-1, etc.1431.Waggott and Davies, 1984Hydrogen; Column length: 50. m; Column diameter: 0.32 mm; Program: not specified

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Mass spectrum (electron ionization), Gas Chromatography, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Colomina, Jimenez, et al., 1989
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of 1,2,4,5-tetramethylbenzene, pentamethylbenzene, and hexamethylbenzene, J. Chem. Thermodyn., 1989, 21, 275-281. [all data]

Boned, Colomina, et al., 1964
Boned, M.L.; Colomina, M.; Perez-Ossorio, R.; Turrion, C., Investigaciones termoquimicas sobre los polimetilbencenos superiores, Anal. Fisc. Quim. B, 1964, 60, 459-468. [all data]

Parks, West, et al., 1946
Parks, G.S.; West, T.J.; Naylor, B.F.; Fujii, P.S.; McClaine, L.A., Thermal data on organic compounds. XXIII. Modern combustion data for fourteen hydrocarbons and five polyhydroxy alcohols, J. Am. Chem. Soc., 1946, 68, 2524-2527. [all data]

Draeger, 1985
Draeger, J.A., The methylbenzenes II. Fundamental vibrational shifts, statistical thermodynamic functions, and properties of formation, J. Chem. Thermodyn., 1985, 17, 263-275. [all data]

Hastings S.H., 1957
Hastings S.H., Thermodynamic properties of selected methylbenzenes from 0 to 1000 K, J. Phys. Chem., 1957, 61, 730-735. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Cooper, Crowne, et al., 1967
Cooper, A.R.; Crowne, C.W.P.; Farrell, P.G., Gas-Liquid Chromatographic Studies of Electron-Donor-Acceptor Systems, Trans. Faraday Soc., 1967, 63, 447. [all data]

Tsonopoulos and Ambrose, 1995
Tsonopoulos, C.; Ambrose, D., Vapor-Liquid Critical Properties of Elements and Compounds. 3. Aromatic Hydrocarbons, J. Chem. Eng. Data, 1995, 40, 547-558. [all data]

Ambrose, Broderick, et al., 1974
Ambrose, D.; Broderick, B.E.; Townsend, R., The Critical Temperatures and Pressures of Thirty Organic Compounds, J. Appl. Chem. Biotechnol., 1974, 24, 359. [all data]

Guye and Mallet, 1902
Guye, P.A.; Mallet, E., Measurement of Critical Constants, Arch. Sci. Phys. Nat., 1902, 13, 274-296. [all data]

Zhao, Unhannanant, et al., 2008
Zhao, Hui; Unhannanant, Patamaporn; Hanshaw, William; Chickos, James S., Enthalpies of Vaporization and Vapor Pressures of Some Deuterated Hydrocarbons. Liquid-Vapor Pressure Isotope Effects, J. Chem. Eng. Data, 2008, 53, 7, 1545-1556, https://doi.org/10.1021/je800091s . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Ambrose, Lawrenson, et al., 1976
Ambrose, D.; Lawrenson, I.J.; Sprake, C.H.S., The vapour pressure of hexamethylbenzene, The Journal of Chemical Thermodynamics, 1976, 8, 5, 503-504, https://doi.org/10.1016/0021-9614(76)90071-9 . [all data]

Overberger, Steele, et al., 1969
Overberger, John E.; Steele, William A.; Aston, John G., The vapor pressure of hexamethylbenzene the standard entropy of hexamethylbenzene vapor and the barrier to internal rotation, The Journal of Chemical Thermodynamics, 1969, 1, 6, 535-542, https://doi.org/10.1016/0021-9614(69)90014-7 . [all data]

Domalski and Hearing, 1996
Domalski, Eugene S.; Hearing, Elizabeth D., Heat Capacities and Entropies of Organic Compounds in the Condensed Phase. Volume III, J. Phys. Chem. Ref. Data, 1996, 25, 1, 1, https://doi.org/10.1063/1.555985 . [all data]

Spaght, Thomas, et al., 1931
Spaght, M.E.; Thomas, S.B.; Parks, G.S., Some Heat-Capacity Data on Organic Compounds obtained with a Radiation Calorimeter, J. Phys. Chem., 1931, 36, 3, 882-888, https://doi.org/10.1021/j150333a009 . [all data]

Fujiwara, Inaba, et al., 1992
Fujiwara, T.; Inaba, A.; Atake, T.; Chihara, H., Thermodynamic properties of deuterated hexamethylbenzene and of its solid solutions with the hydrogenated analog. A large isotope effect on the phase transition at the temperature 117 K, J. Chem. Thermodynam., 1992, 24, 863-881. [all data]

Atake, Gyoten, et al., 1982
Atake, T.; Gyoten, H.; Chihara, H., A concealed anomaly at 117.5 K in the heat capacity of hexamethylbenzene, J. Chem. Phys., 1982, 76(11), 5535-5540. [all data]

Petropavlov, Tsygankova, et al., 1988
Petropavlov, N.N.; Tsygankova, I.G.; Teslenko, L.A., Microcalorimetric investigation of polymorphic transitions in organic crystals, Sov. Phys. Crystallogr., 1988, 33(6), 853-855. [all data]

Yoshimoto, Fujiwara, et al., 1985
Yoshimoto, Y.; Fujiwara, T.; Atake, T.; Chihara, H., Solid-solid transition in hexamethylbenzene that depends on thermal history, Chem. Lett., 1985, (9), 1347-1350. [all data]

Frankosky and Aston, 1965
Frankosky, M.; Aston, J.G., The heat capacity and entropy of hexamethylbenzene from 13 to 340 K. An estimate of the internal rotation barrier, J. Phys. Chem., 1965, 69, 3126-3132. [all data]

Momotani, Suga, et al., 1956
Momotani, M.; Suga, H.; Seki, S.; Nitta, I., Phase transitions in crystals composed of organic molecules with methyl groups at the molecular periperies, Proceed. National Academy of Sci. (India), XXV(Section A, part, 1956, II), 74-82. [all data]

Spaght, Thomas, et al., 1932
Spaght, M.E.; Thomas, S.B.; Parks, G.S., Some heat capacity data on organic compounds obtained with a radiation calorimeter, J. Phys. Chem., 1932, 36, 882-888. [all data]

Huffman, Parks, et al., 1930
Huffman, H.M.; Parks, G.S.; Daniels, A.C., Thermal data on organic compounds. VII. The heat capacities, entropies and free energies of twelve aromatic hydrocarbons, J. Am. Chem. Soc., 1930, 52, 1547-1558. [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 thermochemistry data, Phase change data, Mass spectrum (electron ionization), Gas Chromatography, References