p-Xylene

• Formula: C₈H₁₀
• Molecular weight: 106.1650
• IUPAC Standard InChI: InChI=1S/C8H10/c1-7-3-5-8(2)6-4-7/h3-6H,1-2H3 Copy

  
• IUPAC Standard InChIKey: URLKBWYHVLBVBO-UHFFFAOYSA-N Copy
• CAS Registry Number: 106-42-3
• 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:
  • 1,4-Di(methyl-d3)benzene-d4
• Other names: Benzene, 1,4-dimethyl-; p-Dimethylbenzene; p-Xylol; 1,4-Dimethylbenzene; 1,4-Xylene; p-Methyltoluene; para-Xylene; Chromar; Scintillar; 4-Methyltoluene; NSC 72419; UN 1307; 1,4-dimethyl-benzene ( p-xylene)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • Ion clustering data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • NIST Polycyclic Aromatic Hydrocarbon Structure Index
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, "lite" edition (thermophysical and thermochemical data)
• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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.

Phase change data

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 as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
BS - Robert L. Brown and Stephen E. Stein
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

Enthalpy of vaporization

Enthalpy of vaporization

Δ_vapH = A exp(-βT_r) (1 − T_r)^β
    Δ_vapH = Enthalpy of vaporization (at saturation pressure) (kJ/mol)
    T_r = reduced temperature (T / T_c)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (bar)
    T = temperature (K)

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Phase change 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 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)
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

View reactions leading to C₈H₁₀⁺ (ion structure unspecified)

Electron affinity determinations

Proton affinity at 298K

Gas basicity at 298K

Protonation entropy at 298K

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

C₈H₉^- +  =

By formula: C₈H₉^- + H⁺ = C₈H₁₀

Ion clustering data

Go To: Top, Phase change data, 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 as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

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

C₃H₉Si⁺ +  = (C₃H₉Si⁺ • )

By formula: C₃H₉Si⁺ + C₈H₁₀ = (C₃H₉Si⁺ • C₈H₁₀)

Free energy of reaction

C₆H₇N⁺ +  = (C₆H₇N⁺ • )

By formula: C₆H₇N⁺ + C₈H₁₀ = (C₆H₇N⁺ • C₈H₁₀)

Bond type: Charge transfer bond (positive ion)

Free energy of reaction

C₈H₁₀⁺ +  = (C₈H₁₀⁺ • )

By formula: C₈H₁₀⁺ + C₈H₁₀ = (C₈H₁₀⁺ • C₈H₁₀)

Bond type: Charge transfer bond (positive ion)

C₉H₁₂⁺ +  = (C₉H₁₂⁺ • )

By formula: C₉H₁₂⁺ + C₈H₁₀ = (C₉H₁₂⁺ • C₈H₁₀)

Bond type: Charge transfer bond (positive ion)

 +  = ( • )

By formula: Cl^- + C₈H₁₀ = (Cl^- • C₈H₁₀)

Free energy of reaction

 +  = ( • )

By formula: Cr⁺ + C₈H₁₀ = (Cr⁺ • C₈H₁₀)

( • ) +  = ( • 2)

By formula: (Cr⁺ • C₈H₁₀) + C₈H₁₀ = (Cr⁺ • 2C₈H₁₀)

References

Go To: Top, Phase change data, Gas phase ion energetics data, Ion clustering data, Notes

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

Messerly, Finke, et al., 1988
Messerly, J.F.; Finke, H.L.; Good, W.D.; Gammon, B.E., Condensed-phase heat capacities and derived thermodynamic properties for 1,4-dimethylbenzene, 1,2-diphenylethane, and 2,3-dimethylnaphthalene, J. Chem. Thermodyn., 1988, 20, 485. [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, 1547-58. [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]

Akhundov and Imanov, 1970
Akhundov, T.S.; Imanov, Sh.Yu., Teplofiz. Svoistva Zhidk., 1970, 1970, 48-55. [all data]

Simon, 1957
Simon, M., Methods and Apparatus Used at the Bureau of Physicochemical Standards XV. Critical Constants and Straight-Line Diameters of Ten Hydrocarbons, Bull. Soc. Chim. Belg., 1957, 66, 375-81. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Hossenlopp and Archer, 1988
Hossenlopp, I.A.; Archer, D.G., Enthalpies of vaporization of piperidine and 1,2-dimethylbenzene; gas-phase isobaric heat capacities of piperidine, The Journal of Chemical Thermodynamics, 1988, 20, 9, 1061-1068, https://doi.org/10.1016/0021-9614(88)90112-7 . [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]

Osborn and Douslin, 1974
Osborn, Ann G.; Douslin, Donald R., Vapor-pressure relations for 15 hydrocarbons, J. Chem. Eng. Data, 1974, 19, 2, 114-117, https://doi.org/10.1021/je60061a022 . [all data]

Natarajan and Viswanath, 1985
Natarajan, Govindarajan; Viswanath, Dabir S., Enthalpy of vaporization and vapor pressure of benzene, toluene, p-xylene, and tetralin between 1 and 16 bar, J. Chem. Eng. Data, 1985, 30, 2, 137-140, https://doi.org/10.1021/je00040a001 . [all data]

Castellari, Francesconi, et al., 1982
Castellari, Carlo; Francesconi, Romolo; Comelli, Fabio, Vapor-liquid equilibriums in binary systems containing 1,3-dioxolane at isobaric conditions. 3. Binary mixtures of 1,3-dioxolane with o-, m-, and p-xylenes, J. Chem. Eng. Data, 1982, 27, 2, 156-158, https://doi.org/10.1021/je00028a017 . [all data]

Gaw and Swinton, 1968
Gaw, W.J.; Swinton, F.L., Thermodynamic properties of binary systems containing hexafluorobenzene. Part 4.?Excess Gibbs free energies of the three systems hexafluorobenzene + benzene, touene, and p-xylene, Trans. Faraday Soc., 1968, 64, 2023, https://doi.org/10.1039/tf9686402023 . [all data]

Willingham, Taylor, et al., 1945
Willingham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D., Vapor pressures and boiling points of some paraffin, alkylcyclopentane, alkylcyclohexane, and alkylbenzene hydrocarbons, J. RES. NATL. BUR. STAN., 1945, 35, 3, 219-17, https://doi.org/10.6028/jres.035.009 . [all data]

Forziati, Norris, et al., 1949
Forziati, Alphonse F.; Norris, William R.; Rossini, Frederick D., Vapor pressures and boiling points of sixty API-NBS hydrocarbons, J. RES. NATL. BUR. STAN., 1949, 43, 6, 555-17, https://doi.org/10.6028/jres.043.050 . [all data]

Ambrose, Broderick, et al., 1967
Ambrose, D.; Broderick, B.E.; Townsend, R., The Vapour Pressures Above the Normal Boiling Point and the Critical Pressures of Some Aromatic Hydrocarbons, J. Chem. Soc. A:, 1967, 633-641, https://doi.org/10.1039/j19670000633 . [all data]

Williamham, Taylor, et al., 1945
Williamham, C.B.; Taylor, W.J.; Pignocco, J.M.; Rossini, F.D., Vapor Pressures and Boiling Points of Some Paraffin, Alkylcyclopentane, Alkylcyclohexane, and Alkylbenzene Hydrocarbons, J. Res. Natl. Bur. Stand. (U.S.), 1945, 35, 3, 219-244, https://doi.org/10.6028/jres.035.009 . [all data]

Pitzer and Scott, 1943
Pitzer, K.S.; Scott, D.W., The thermodynamics and molecular structure of benzene and its methyl derivatives, J. Am. Chem. Soc., 1943, 65, 803-829. [all data]

Hessler and Lichtenstein, 1986
Hessler, W.; Lichtenstein, W., Wiss. Zeitschr. Wilhelm-Pieck-Univ. Rostock, Naturwiss. Reihe, 1986, 35, 7, 27. [all data]

Messerly, Finke, et al., 1988, 2
Messerly, J.F.; Finke, H.L.; Good, W.D.; Gammon, B.E., Condensed-phase heat capacities and derived thermodynamic properties for 1,4-dimethylbenzene, 1,2-diphenylethane, and 2,3-dimethylnaphthalene, J. Chem. Thermodynam., 1988, 20, 485-501. [all data]

Corruccini and Ginnings, 1947
Corruccini, R.J.; Ginnings, D.C., The enthalpy, entropy and specific heat of liquid p-xylene from 0 to 300°. The heat of fusion, J. Am. Chem. Soc., 1947, 69, 2291-2294. [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]

Huffman, Parks, et al., 1930, 2
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]

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]

Hammer, Diri, et al., 2003
Hammer, N.I.; Diri, K.; Jordan, K.D.; Desfrancois, C.; Compton, R.N., Dipole-bound anions of carbonyl, nitrile, and sulfoxide containing molecules, J. Chem. Phys., 2003, 119, 7, 3650-3660, https://doi.org/10.1063/1.1590959 . [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]

Fernandez, Jennings, et al., 1989
Fernandez, T.; Jennings, K.R.; Mason, R.S., Gas-phase proton transfer reactions in xylene-dimethyl ether mixtures, J. Chem. Soc. Faraday Trans. 2, 1989, 85, 1813. [all data]

Lias and Ausloos, 1978
Lias, S.G.; Ausloos, P.J., eIonization energies of organic compounds by equilibrium measurements, J. Am. Chem. Soc., 1978, 100, 6027. [all data]

Bock, Kaim, et al., 1978
Bock, H.; Kaim, W.; Rohwer, H.E., Die hyperkonjugative Stabilisierung von p-Xylol-Radikalkationen durch (H₃C)₃Si-Substituenten, Chem. Ber., 1978, 111, 3573. [all data]

Loudon and Mazengo, 1974
Loudon, A.G.; Mazengo, R.Z., Steric strain and electron-impact. The behaviour of some n, n'-dimethyl- 1,1-binaphthyls, some n, n'-dimethylbiphenyls and model compounds, Org. Mass Spectrom., 1974, 8, 179. [all data]

Maier and Turner, 1973
Maier, J.P.; Turner, D.W., Steric inhibition of resonance studied by molecular photoelectron spectroscopy. Part 2. Phenylethylenes, J. Chem. Soc. Faraday Trans. 2, 1973, 69, 196. [all data]

Kinoshita, 1962
Kinoshita, M., The absorption spectra of the molecular complexes of aromatic compounds with p-bromanil, Bull. Chem. Soc. Japan, 1962, 35, 1609. [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]

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]

Watanabe, 1954
Watanabe, K., Photoionization and total absorption cross section of gases. I. Ionization potentials of several molecules. Cross sections of NH₃ and NO, J. Chem. Phys., 1954, 22, 1564. [all data]

Hammond, Price, et al., 1950
Hammond, V.J.; Price, W.C.; Teegan, J.P.; Walsh, A.D., The absorption spectra of some substituted benzenes and naphthalenes in the vacuum ultra-violet, Faraday Discuss. Chem. Soc., 1950, 9, 53. [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]

Koenig, Tuttle, et al., 1974
Koenig, T.; Tuttle, M.; Wielesek, R.A., The He(I) photoelectron spectra of xylenes and metacyclophanes. A reassignment of the lowest ionic state of [2.2] metacyclophane, Tetrahedron Lett., 1974, 2537. [all data]

Klessinger, 1972
Klessinger, M., Ionization potentials of substituted benzenes, Angew. Chem. Int. Ed. Engl., 1972, 11, 525. [all data]

Tajima and Tsuchiya, 1973
Tajima, S.; Tsuchiya, T., Energetics consideration of C₅H₅⁺ ions produced from various precursors by electron impact, Bull. Chem. Soc. Jpn., 1973, 46, 3291. [all data]

McLafferty and Winkler, 1974
McLafferty, F.W.; Winkler, J., Gaseous tropylium, benzyl, tolyl, and norbornadienyl cations, J. Am. Chem. Soc., 1974, 96, 5182. [all data]

Akopyan and Vilesov, 1968
Akopyan, M.E.; Vilesov, F.I., Mass-spectrometric investigation of the photo-ionization of benzene and its methyl derivatives, Khim. Vysokikh Energ., 1968, 2, 107, In original 89. [all data]

Nounou, 1966
Nounou, P., Etude des composes aromatiques par spectrometrie de masse. I. Mesure des potentials d'ionisation et d'apparition par la methode du potential retardateur et interpretation des courbes d'ionisation differentielle, J. Chim. Phys., 1966, 63, 994. [all data]

Tait, Shannon, et al., 1962
Tait, J.M.S.; Shannon, T.W.; Harrison, A.G., The structure of substituted C₇ ions from benzyl derivatives at the appearance potential threshold, J. Am. Chem. Soc., 1962, 84, 4. [all data]

Bartmess, Scott, et al., 1979
Bartmess, J.E.; Scott, J.A.; McIver, R.T., Jr., The gas phase acidity scale from methanol to phenol, J. Am. Chem. Soc., 1979, 101, 6047. [all data]

Wojtyniak and Stone, 1986
Wojtyniak, A.C.M.; Stone, A.J., A High-Pressure Mass Spectrometric Study of the Bonding of Trimethylsilylium to Oxygen and Aromatic Bases, Can. J. Chem., 1986, 74, 59. [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]

Meot-Ner (Mautner), Hamlet, et al., 1978
Meot-Ner (Mautner), M.; Hamlet, P.; Hunter, E.P.; Field, F.H., Bonding Energies in Association Ions of Aromatic Molecules. Correlations with Ionization Energies, J. Am. Chem. Soc., 1978, 100, 17, 5466, https://doi.org/10.1021/ja00485a034 . [all data]

French, Ikuta, et al., 1982
French, M.A.; Ikuta, S.; Kebarle, P., Hydrogen bonding of O-H and C-H hydrogen donors to Cl^-. Results from mass spectrometric measurement of the ion-molecule equilibria RH + Cl^- = RHCl^-, Can. J. Chem., 1982, 60, 1907. [all data]

Lin and Dunbar, 1997
Lin, C.-Y.; Dunbar, R.C., Radiative Association Kinetics and Binding Energies of Chromium Ions with Benzene and Benzene Derivatives, Organometallics, 1997, 16, 12, 2691, https://doi.org/10.1021/om960949n . [all data]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, Ion clustering data, References

• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  Pc	Critical pressure
  T	Temperature
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  Vc	Critical volume
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.