o-Xylene

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

  
• IUPAC Standard InChIKey: CTQNGGLPUBDAKN-UHFFFAOYSA-N Copy
• CAS Registry Number: 95-47-6
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  View 3d structure (requires JavaScript / HTML 5)
• Isotopologues:
  • 1,2-Di(methyl-d3)benzene-d4
• Other names: Benzene, 1,2-dimethyl-; o-Dimethylbenzene; o-Methyltoluene; o-Xylol; 1,2-Dimethylbenzene; 1,2-Xylene; 3,4-Xylene; ortho-Xylene; NSC 60920; 2-Methyltoluene; UN 1307; 1,2-dimethyl-benzene ( o-xylene)
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Gas Phase Kinetics Database
• Options:
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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Constant pressure heat capacity of gas

Constant pressure heat capacity of gas

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry 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:
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)

Proton affinity at 298K

Gas basicity at 298K

Protonation entropy at 298K

Ionization energy determinations

Appearance energy determinations

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Notes

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

Prosen, Gilmont, et al., 1945
Prosen, E.J.; Gilmont, R.; Rossini, F.D., Heats of combustion of benzene, toluene, ethyl-benzene, o-xylene, m-xylene, p-xylene, n-propylbenzene, and styrene, J. Res. NBS, 1945, 34, 65-70. [all data]

Prosen, Johnson, et al., 1946
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heats of combustion and formation at 25°C of the alkylbenzenes through C₁₀H₁₄, and of the higher normal monoalkylbenzenes, J. Res. NBS, 1946, 36, 455-461. [all data]

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

Taylor W.J., 1946
Taylor W.J., Heats, equilibrium constants, and free energies of formation of the alkylbenzenes, J. Res. Nat. Bur. Stand., 1946, 37, 95-122. [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]

Chao J., 1984
Chao J., Chemical thermodynamic properties of toluene, o-, m- and p-xylenes, Thermochim. Acta, 1984, 72, 323-334. [all data]

Coops, Mulder, et al., 1946
Coops, J.; Mulder, D.; Dienske, J.W.; Smittenberg, J., The heats of combustion of a number of hydrocarbons, Rec. Trav. Chim. Pays/Bas, 1946, 65, 128. [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]

Richards and Barry, 1915
Richards, T.W.; Barry, F., The heats of combustion of aromatic hydrocarbons and hexamethylene, J. Am. Chem. Soc., 1915, 37, 993-1020. [all data]

Richards and Jesse, 1910
Richards, T.W.; Jesse, R.H., Jr., The heats of combustion of the octanes and xylenes, J. Am. Chem. Soc., 1910, 32, 268-298. [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]

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]

Fortier and Benson, 1979
Fortier, J.-L.; Benson, G.C., Heat capacities of some binary aromatic hydrocarbon mixtures containing benzene or toluene, J. Chem. Eng. Data, 1979, 24(1), 34-37. [all data]

Fortier and Benson, 1977
Fortier, J.-L.; Benson, G.C., Excess heat capacities of binary mixtures of tetrachloromethane witlh some aromatic liquids at 298.15 K, J. Chem. Thermodynam., 1977, 9, 1181-1188. [all data]

Swietoslawski and Zielenkiewicz, 1958
Swietoslawski, W.; Zielenkiewicz, A., Mean specific heats of binary positive azeotropes, Bull. Acad. Pol. Sci. Ser. Sci. Chim., 1958, 6, 367-369. [all data]

Kurbatov, 1947
Kurbatov, V.Ya., Specific heat of liquids. I. Specific heat of benzenoid hydrocarbons, Zhur. Obshch. Khim., 1947, 17, 1999-2003. [all data]

Willams and Daniels, 1924
Willams, J.W.; Daniels, F., The specific heats of certain organic liquids at elevated temperatures, J. Am. Chem. Soc., 1924, 46, 903-917. [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]

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]

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]

Kobayashi, Kobayashi, et al., 1973
Kobayashi, H.; Kobayashi, M.; Kaizu, Y., Molecular complexes of arenetricarbonylchromium, Bull. Chem. Soc. Jpn., 1973, 46, 3109. [all data]

Gilbert, Leach, et al., 1973
Gilbert, J.R.; Leach, W.P.; Miller, J.R., Ionisation appearance potential measurements in arene chromium tricarbonyls, J. Organomet. Chem., 1973, 49, 219. [all data]

Pitt, 1970
Pitt, C.G., Hyperconjugation: An alternative to the concept of the p_π-d_π bond in Group IV chemistry, J. Organomet. Chem., 1970, 23, 35. [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]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [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]

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]

Heilbronner, Hoshi, et al., 1976
Heilbronner, E.; Hoshi, T.; von Rosenberg, J.L.; Hafner, K., Alkyl-induced, natural hypsochromic shifts of the ²A←²X and ²B←²X transitions of azulene and naphthalene radical cations, Nouv. J. Chim., 1976, 1, 105. [all data]

Brogli, Giovannini, et al., 1973
Brogli, F.; Giovannini, E.; Heilbronner, E.; Schurter, R., Die photoelektronen spektren der benzocycloalkene, Chem. Ber., 1973, 106, 961. [all data]

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

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,gas	Constant pressure heat capacity of gas
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°gas	Entropy of gas at standard conditions
  S°liquid	Entropy of liquid at standard conditions
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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