α-Methylstyrene

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Gas 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
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas28.27 ± 0.34kcal/molEqkGuthrie, 1978ALS
Quantity Value Units Method Reference Comment
Δcgas-1215.05kcal/molCcbKrall and Roberts, 1958Corresponding Δfgas = 27.01 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of gas

Cp,gas (cal/mol*K) Temperature (K) Reference Comment
10.8850.Thermodynamics Research Center, 1997p=1 bar.; GT
13.72100.
17.63150.
22.50200.
30.679273.15
33.578298.15
33.791300.
44.857400.
54.271500.
61.93600.
68.14700.
73.26800.
77.51900.
81.091000.
84.131100.
86.691200.
88.891300.
90.771400.
92.381500.

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
Δcliquid-1204.87kcal/molCcbRoberts and Jessup, 1951Corresponding Δfliquid = 16.83 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-1217.3kcal/molCcbLemoult, 1911Corresponding Δfliquid = 29.3 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Δcliquid-1195.1kcal/molCcbAuwsers, Roth, et al., 1910Corresponding Δfliquid = 7.1 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS
Quantity Value Units Method Reference Comment
liquid58.27cal/mol*KN/ALebedev and Rabinovich, 1971DH

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
48.33300.Lebedev and Rabinovich, 1971T = 60 to 300 K.; DH

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics 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 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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil438. ± 4.KAVGN/AAverage of 15 out of 16 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus249.05KN/AAnonymous, 1952Uncertainty assigned by TRC = 0.3 K; TRC
Tfus247.22KN/AAnonymous, 1946Uncertainty assigned by TRC = 0.6 K; TRC
Tfus249.94KN/AStull, 1945Uncertainty assigned by TRC = 0.25 K; TRC
Tfus244.83KN/AAnonymous, 1943Uncertainty assigned by TRC = 0.4 K; TRC
Quantity Value Units Method Reference Comment
Tc645.KN/ASteele, Chirico, et al., 1997Uncertainty assigned by TRC = 6. K; TRC
Quantity Value Units Method Reference Comment
Pc35.04atmN/ASteele, Chirico, et al., 1997Uncertainty assigned by TRC = 2.96 atm; derived from fit of obs. vapor pressure; TRC
Quantity Value Units Method Reference Comment
ρc2.44mol/lN/ASteele, Chirico, et al., 1997Uncertainty assigned by TRC = 0.13 mol/l; TRC
Quantity Value Units Method Reference Comment
Δvap11.7 ± 0.07kcal/molGSVerevkin, 1999Based on data from 274. to 314. K.; AC
Δvap11.6 ± 0.1kcal/molEBSteele, Chirico, et al., 1997, 2Based on data from 331. to 467. K.; AC

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
11.8 ± 0.07294.GSVerevkin, 1999Based on data from 274. to 314. K.; AC
11.0 ± 0.07340.EBSteele, Chirico, et al., 1997, 2Based on data from 331. to 467. K.; AC
10.3 ± 0.07380.EBSteele, Chirico, et al., 1997, 2Based on data from 331. to 467. K.; AC
9.70 ± 0.07420.EBSteele, Chirico, et al., 1997, 2Based on data from 331. to 467. K.; AC
9.0 ± 0.1460.EBSteele, Chirico, et al., 1997, 2Based on data from 331. to 467. K.; AC
10.6358.AStephenson and Malanowski, 1987Based on data from 343. to 493. K.; AC
10.7368.AStephenson and Malanowski, 1987Based on data from 353. to 413. K.; AC

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
280.6 to 438.65.213962326.8677.23Stull, 1947Coefficents calculated by NIST from author's data.

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
2.8499250.78Lebedev and Rabinovich, 1971DH
2.849250.8Domalski and Hearing, 1996AC

Entropy of fusion

ΔfusS (cal/mol*K) Temperature (K) Reference Comment
11.36250.78Lebedev and Rabinovich, 1971DH

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, 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 as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
B - John E. Bartmess

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

Hydrogen chloride + α-Methylstyrene = Benzene, (1-chloro-1-methylethyl)-

By formula: HCl + C9H10 = C9H11Cl

Quantity Value Units Method Reference Comment
Δr-8.80 ± 0.45kcal/molCmArnett and Pienta, 1980liquid phase; solvent: Methylene chloride; Hydrochlorination; ALS
Δr-12.4 ± 1.1kcal/molCmNesterova, Kovzel, et al., 1977liquid phase; Hydrochlorination; ALS

C9H9- + Hydrogen cation = α-Methylstyrene

By formula: C9H9- + H+ = C9H10

Quantity Value Units Method Reference Comment
Δr385.6 ± 5.6kcal/molG+TSBartmess and Burnham, 1984gas phase; between H2O, MeOH; B
Quantity Value Units Method Reference Comment
Δr379.0 ± 5.5kcal/molIMRBBartmess and Burnham, 1984gas phase; between H2O, MeOH; B

Hydrogen + α-Methylstyrene = Benzene, (1-methylethyl)-

By formula: H2 + C9H10 = C9H12

Quantity Value Units Method Reference Comment
Δr-26.60 ± 0.50kcal/molChydAbboud, Jimenez, et al., 1995liquid phase; solvent: Hyrocarbon; Like gas phase; ALS

Hydrogen bromide + α-Methylstyrene = Benzene, (1-bromo-1-methylethyl)-

By formula: HBr + C9H10 = C9H11Br

Quantity Value Units Method Reference Comment
Δr-15.2 ± 1.3kcal/molCmNesterova, Kovzel, et al., 1977liquid phase; Hydrobromination; ALS

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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 C9H10+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
Proton affinity (review)206.5kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity199.6kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.3 ± 0.1EIKoppel, Schwarz, et al., 1974LLK
8.18 ± 0.04EIBenito, Seidl, et al., 1973LLK
8.35 ± 0.01PIWatanabe, Nakayama, et al., 1962RDSH
8.50PEChizhov, Timoshenko, et al., 1986Vertical value; LBLHLM
8.52PEKobayashi, Yokota, et al., 1973Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C9H9+11.8 ± 0.1HEIKoppel, Schwarz, et al., 1974LLK

De-protonation reactions

C9H9- + Hydrogen cation = α-Methylstyrene

By formula: C9H9- + H+ = C9H10

Quantity Value Units Method Reference Comment
Δr385.6 ± 5.6kcal/molG+TSBartmess and Burnham, 1984gas phase; between H2O, MeOH; B
Quantity Value Units Method Reference Comment
Δr379.0 ± 5.5kcal/molIMRBBartmess and Burnham, 1984gas phase; between H2O, MeOH; B

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, 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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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-2072
NIST MS number 229186

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References

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), Notes

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

Guthrie, 1978
Guthrie, J.P., Equilibrium constants for a series of simple aldol condensations, and linear free energy relations with other carbonyl addition reactions, Can. J. Chem., 1978, 56, 962-973. [all data]

Krall and Roberts, 1958
Krall, R.E.; Roberts, J.D., Strain variation in the unsaturated cyclobutane ring, Am. Chem. Soc. Div. Pet. Chem., 1958, 3, 63-68. [all data]

Thermodynamics Research Center, 1997
Thermodynamics Research Center, Selected Values of Properties of Chemical Compounds., Thermodynamics Research Center, Texas A&M University, College Station, Texas, 1997. [all data]

Roberts and Jessup, 1951
Roberts, D.E.; Jessup, R.S., Heat of polymerization of alpha-methylstyrene from heats of combustion of monomer and four polymer fractions, J. Res. NBS, 1951, 46, 11-17. [all data]

Lemoult, 1911
Lemoult, M.P., Thermochimie. - Recherches sur les derives du styrolene; rectification de quelques erreurs experimentales, Compt. Rend., 1911, 152, 1402-1404. [all data]

Auwsers, Roth, et al., 1910
Auwsers, K.; Roth, W.A.; Eisenlohr, F., III. Verbrennungswarmen von Terpenen und Styrolen, Justus Liebigs Ann. Chem., 1910, 267-290. [all data]

Lebedev and Rabinovich, 1971
Lebedev, B.V.; Rabinovich, I.B., Heat capacities and thermodynamic functions of a-methylstyrene and poly(a-methylstyrene), Tr. Khim. Khim. Tekhnol., 1971, 1, 12-15. [all data]

Anonymous, 1952
Anonymous, R., , Physical Properties of Chemical Substances, Dow Chemical Co., 1952. [all data]

Anonymous, 1946
Anonymous, R., , Am. Pet. Inst. Res. Proj. 45, Ohio State Univ., 1946. [all data]

Stull, 1945
Stull, D.R., Personal Commun., Dow Chemical Co., 1945. [all data]

Anonymous, 1943
Anonymous, R., , Sunbury Rep. No. 2176, Anglo-Iranian Oil Co., 1943. [all data]

Steele, Chirico, et al., 1997
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A., Vapor Pressure, Heat Capacity, and Density along the Saturated Line, Measurements for Dimethyl Isophthalate, Dimethyl Carbonate, 1,3,5-Trimethyl benzene, Pentafluorophenol, 4-tert-Butylcatechol, .alp, J. Chem. Eng. Data, 1997, 42, 1008-20. [all data]

Verevkin, 1999
Verevkin, Sergey P., Thermochemical investigation on α-methyl-styrene and parent phenyl substituted alkenes, Thermochimica Acta, 1999, 326, 1-2, 17-25, https://doi.org/10.1016/S0040-6031(98)00585-1 . [all data]

Steele, Chirico, et al., 1997, 2
Steele, W.V.; Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A., Vapor Pressure, Heat Capacity, and Density along the Saturation Line, Measurements for Dimethyl Isophthalate, Dimethyl Carbonate, 1,3,5-Triethylbenzene, Pentafluorophenol, 4- tert -Butylcatechol, α-Methylstyrene, and N , N '-Bis(2-hydroxyethyl)ethylenediamine, J. Chem. Eng. Data, 1997, 42, 6, 1008-1020, https://doi.org/10.1021/je970102d . [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]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [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]

Arnett and Pienta, 1980
Arnett, E.M.; Pienta, N.J., Stabilities of carbonium ions in solution. 12. Heats of formation of alkyl chlorides as an entree to heats of solvation of aliphatic carbonium ions, J. Am. Chem. Soc., 1980, 102, 3329-3334. [all data]

Nesterova, Kovzel, et al., 1977
Nesterova, T.N.; Kovzel, E.N.; Karaseva, S.Ya.; Rozhnov, A.M., Heats of reaction of the hydrohalogenation of styrene and α-methylstyrene, Vses. Konf. Kalorim. Rasshir. Tezisy Dokl. 7th, 1977, 1, 132. [all data]

Bartmess and Burnham, 1984
Bartmess, J.E.; Burnham, R., Effect of central substituents on the gas phase acidities of propenes, J. Org. Chem., 1984, 49, 1382. [all data]

Abboud, Jimenez, et al., 1995
Abboud, J.-L.M.; Jimenez, P.; Roux, M.V.; Turrion, C.; Lopez-Mardomingo, C.; Podosenin, A.; Rogers, D.W.; Liebman, J.F., Interrelations of the energetics of amides and alkenes: enthalpies of formation of N,N-dimethyl dertivatives of pivalamide, 1-adamantylcarboxamide and benzamide, and of styrene and its a-, trans-β- and β,β-methylated derivates, J. Phys. Org. Chem., 1995, 8, 15-25. [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]

Koppel, Schwarz, et al., 1974
Koppel, C.; Schwarz, H.; Bohlmann, F., Elektronenstossinduzierte fragmentierung von acetylenverbindungen. VIII. Struktur der stabilen und instabilen ionen[C9H9]+ aus isomeren C9H10- kohlenwasserstoffen, Org. Mass Spectrom., 1974, 8, 25. [all data]

Benito, Seidl, et al., 1973
Benito, I.; Seidl, H.; Bock, H., Efectos electronicos y estericos de sustituyentes alquilicos y silicicos sobre el sistema electronico π del estireno, Rev. Fac. Cienc. Univ. Oviedo, 1973, 14, 95. [all data]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Chizhov, Timoshenko, et al., 1986
Chizhov, Y.V.; Timoshenko, M.M.; Kleimenov, V.I.; Borisov, Y.A.; Zol'nikova, G.P.; Kravtsov, D.N.; Kritskaya, I.I., Investigation of the mechanism of fragment coordination of aromatic molecules with transition metals by photoelectron spectroscopy - tricarbonyliron complexes, J. Struct. Chem., 1986, 27, 401. [all data]

Kobayashi, Yokota, et al., 1973
Kobayashi, T.; Yokota, K.; Nagakura, S., Photoelectron spectra of styrenes, J. Electron Spectrosc. Relat. Phenom., 1973, 3, 449. [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, Mass spectrum (electron ionization), References