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Benzene, pentamethyl-

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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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
Deltafgas-67.2 ± 2.2kJ/molCcbColomina, Jimenez, et al., 1989see Boned, Colomina, et al., 1964; ALS
Deltafgas-57.7kJ/molN/AParks, West, et al., 1946Value computed using «DELTA»fHsolid° value of -135.1±2.6 kj/mol from Parks, West, et al., 1946 and «DELTA»subH° value of 77.4 kj/mol from Colomina, Jimenez, et al., 1989.; DRB

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
162.3200.Draeger, 1985There is an appreciable difference between values of S(T) and Cp(T) for tetra-, penta-, and hexamethylbenzene from earlier statistical thermodynamics calculation [ Hastings S.H., 1957] and those obtained by [ Draeger, 1985] (up to 5, 9, and 16 J/mol*K, respectively). Results [ Draeger, 1985] are more reliable and they agree with experimental data for hexamethylbenzene.; GT
199.7273.15
212.5 ± 0.4298.15
213.4300.
264.4400.
311.4500.
352.3600.
387.4700.
417.5800.
443.4900.
465.61000.
484.81100.
501.31200.
515.61300.
527.91400.
538.71500.

Condensed phase thermochemistry data

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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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Deltacliquid-6475.6 ± 6.3kJ/molCcbBanse and Parks, 1933Reanalyzed by Cox and Pilcher, 1970, Original value = -6470.64 kJ/mol; Corresponding «DELTA»fliquid = -139.7 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
Deltafsolid-144.6 ± 2.2kJ/molCcbColomina, Jimenez, et al., 1989see Boned, Colomina, et al., 1964; ALS
Deltafsolid-135.1 ± 2.6kJ/molCcbParks, West, et al., 1946Reanalyzed by Cox and Pilcher, 1970, Original value = -135.7 ± 0.04 kJ/mol; ALS
Quantity Value Units Method Reference Comment
Deltacsolid-6470.6 ± 1.6kJ/molCcbColomina, Jimenez, et al., 1989see Boned, Colomina, et al., 1964; Corresponding «DELTA»fsolid = -144.7 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Deltacsolid-6480.1 ± 2.6kJ/molCcbParks, West, et al., 1946Reanalyzed by Cox and Pilcher, 1970, Original value = -6479.6 ± 2.6 kJ/mol; Corresponding «DELTA»fsolid = -135.1 kJ/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
solid,1 bar294.1J/mol*KN/AHuffman, Parks, et al., 1931crystaline, I phase; Extrapolation below 90 K, 102.9 J/mol*K.; DH

Constant pressure heat capacity of solid

Cp,solid (J/mol*K) Temperature (K) Reference Comment
210.5298.15Colomina, Jimenez, et al., 1989DH
270.3298.1Eibert, 1944crystaline, I phase; T = 25 to 200°C, equations only, in t°C. Cp(c) = 0.3914 + 0.001760t cal/g*K (25 to 40°C); Cp(liq) = 0.432 + 0.000425 t cal/g*K (55 to 200°C).; DH
267.3303.Ferry and Thomas, 1933T = 303 to 393 K.; DH
251.0283.8Huffman, Parks, et al., 1931crystaline, I phase; T = 92 to 304 K. Value is unsmoothed experimental datum.; DH

Phase change data

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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.
DH - Eugene S. Domalski and Elizabeth D. Hearing
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

Quantity Value Units Method Reference Comment
Tboil510. ± 20.KAVGN/AAverage of 10 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus326. ± 3.KAVGN/AAverage of 17 values; Individual data points
Quantity Value Units Method Reference Comment
Deltasub71.60 ± 0.10kJ/molCSabbah, Tabet, et al., 1994ALS
Deltasub71.6 ± 0.1kJ/molCSabbah, Tabet, et al., 1994AC
Deltasub77.4 ± 0.4kJ/molVColomina, Jimenez, et al., 1989see Boned, Colomina, et al., 1964; ALS
Deltasub77.4kJ/molN/AColomina, Jimenez, et al., 1989DRB
Deltasub77.4 ± 0.4kJ/molMEColomina, Jimenez, et al., 1989Based on data from 296. - 313. K.; AC

Enthalpy of vaporization

DeltavapH (kJ/mol) Temperature (K) Method Reference Comment
57.8353.AStephenson and Malanowski, 1987Based on data from 338. - 503. K.; AC

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
10.67328.2Domalski and Hearing, 1996AC
10.670328.2Eibert, 1944DH

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
32.5328.2Eibert, 1944DH

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
6.67296.8Domalski and Hearing, 1996CAL
32.51328.2

Enthalpy of phase transition

DeltaHtrs (kJ/mol) Temperature (K) Initial Phase Final Phase Reference Comment
1.799296.35crystaline, IIcrystaline, IFerry and Thomas, 1933DH
12.343327.45crystaline, IliquidFerry and Thomas, 1933DH
1.979296.8crystaline, IIcrystaline, IHuffman, Parks, et al., 1931DH

Entropy of phase transition

DeltaStrs (J/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
6.7296.8crystaline, IIcrystaline, IHuffman, Parks, et al., 1931DH

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:


Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

1,3,4,5-Tetramethyl-2-methylenebicyclo[3.1.0]hex-3-ene = Benzene, pentamethyl-

By formula: C11H16 = C11H16

Quantity Value Units Method Reference Comment
Deltar-136. ± 3.kJ/molCisoChilds and Mulholland, 1983liquid phase

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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

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
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess

View reactions leading to C11H16+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)850.7kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity823.5kJ/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
<0.182 ± 0.013ECDWojnarovits and Foldiak, 1981EA is an upper limit: Chen and Wentworth, 1989,. G3MP2B3 calculations indicate an EA of ca. -0.5 eV, anion unbound.; B

Ionization energy determinations

IE (eV) Method Reference Comment
7.92PEHowell, Goncalves, et al., 1984LBLHLM
7.92PIBralsford, Harris, et al., 1960RDSH
7.9CTSFoster, 1959RDSH
7.92 ± 0.02PIVilesov and Terenin, 1957RDSH
7.92PEHowell, Goncalves, et al., 1984Vertical value; LBLHLM

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, References, Notes

Data compiled by: Coblentz Society, Inc.

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director


Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, UV/Visible spectrum, 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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Mass spectrum
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Additional Data

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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-4461
NIST MS number 230550

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.


UV/Visible spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Additional Data

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Source Kusakov, et al., 1963
Owner INEP CP RAS, NIST OSRD
Collection (C) 2007 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS
Source reference RAS UV No. 20049
Instrument unknown
Melting point 54.5
Boiling point 232

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, 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]

Banse and Parks, 1933
Banse, H.; Parks, G.S., Thermal data on organic compounds. XII. The heats of combustion of nine hydrocarbons, J. Am. Chem. Soc., 1933, 55, 3223-3227. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Huffman, Parks, et al., 1931
Huffman, H.M.; Parks, G.S.; Barmore, M., Thermal data on organic compounds. X. Further studies on the heat capacities, entropies and free energies of hydrocarbons, J. Am. Chem. Soc., 1931, 53, 3876-3888. [all data]

Eibert, 1944
Eibert, J., Thesis Washington University (St. Louis), 1944. [all data]

Ferry and Thomas, 1933
Ferry, J.D.; Thomas, S.B., Some heat capacity data for durene, pentamethylbenzene, stilbene, and dibenzyl, J. Phys. Chem., 1933, 37, 253-255. [all data]

Sabbah, Tabet, et al., 1994
Sabbah, R.; Tabet, D.; Belaadi, S., Enthalpie de sublimation ou vaporisation de quelques derives methyles du benzene, Thermochim. Acta, 1994, 247, 193-199. [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]

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]

Childs and Mulholland, 1983
Childs, R.F.; Mulholland, D.L., Thermochemical relationships between some bicyclohexenyl and benzenium cations, J. Am. Chem. Soc., 1983, 105, 96-99. [all data]

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 «pi»-complexes with metals. Comparison of the standard oxidation potentials and vertical ionization potentials, J. Am. Chem. Soc., 1984, 106, 3968. [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]

Vilesov and Terenin, 1957
Vilesov, F.I.; Terenin, A.N., The photoionization of the vapors of certain organic compounds, Dokl. Akad. Nauk SSSR, 1957, 115, 744, In original 539. [all data]

Kusakov, et al., 1963
Kusakov, M.M., et al., Ultraviolet Absorption Spectra of Aromatic Hydrocarbons, 1963, 100. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), UV/Visible spectrum, References