Benzene, 1,3-dimethyl-

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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
Δfgas17.2 ± 0.75kJ/molCcbProsen, Johnson, et al., 1946ALS
Quantity Value Units Method Reference Comment
gas358.2 ± 1.3J/mol*KN/APitzer K.S., 1943GT

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
87.21200.Draeger, 1985Discrepancies with other statistically calculated values of S(T) and Cp(T) [ Pitzer K.S., 1943, Taylor W.J., 1946, Hastings S.H., 1957, Chao J., 1984] do not exceed 1.5 J/mol*K.; GT
115.6273.15
125.8 ± 0.4298.15
126.6300.
167.1400.
202.9500.
232.8600.
257.7700.
278.6800.
296.2900.
311.21000.
324.11100.
335.11200.
344.61300.
352.81400.
359.81500.

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
163.6 ± 1.7393.Taylor W.J., 1946Please also see Pitzer K.S., 1943.; GT
177.4 ± 1.7428.
190.0 ± 1.7463.

Reaction 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
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

C3H9Si+ + Benzene, 1,3-dimethyl- = (C3H9Si+ • Benzene, 1,3-dimethyl-)

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

Quantity Value Units Method Reference Comment
Δr121.kJ/molPHPMSWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr147.J/mol*KN/AWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
53.1468.PHPMSWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M

C9H12+ + Benzene, 1,3-dimethyl- = (C9H12+ • Benzene, 1,3-dimethyl-)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Δr59.8kJ/molPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr110.J/mol*KN/AMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
26.300.PHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

C8H9- + Hydrogen cation = Benzene, 1,3-dimethyl-

By formula: C8H9- + H+ = C8H10

Quantity Value Units Method Reference Comment
Δr1594. ± 11.kJ/molG+TSCaldwell and Bartmessgas phase; value altered from reference due to change in acidity scale; B
Quantity Value Units Method Reference Comment
Δr1564. ± 10.kJ/molIMRECaldwell and Bartmessgas phase; value altered from reference due to change in acidity scale; B

Chlorine anion + Benzene, 1,3-dimethyl- = (Chlorine anion • Benzene, 1,3-dimethyl-)

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

Quantity Value Units Method Reference Comment
Δr16.3kJ/molTDEqFrench, Ikuta, et al., 1982gas phase; B

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
18.300.PHPMSFrench, Ikuta, et al., 1982gas phase; M

Ion clustering 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:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess

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+ + Benzene, 1,3-dimethyl- = (C3H9Si+ • Benzene, 1,3-dimethyl-)

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

Quantity Value Units Method Reference Comment
Δr121.kJ/molPHPMSWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr147.J/mol*KN/AWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
53.1468.PHPMSWojtyniak and Stone, 1986gas phase; switching reaction,Thermochemical ladder((CH3)3Si+)C6H6, Entropy change calculated or estimated; M

C9H12+ + Benzene, 1,3-dimethyl- = (C9H12+ • Benzene, 1,3-dimethyl-)

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

Bond type: Charge transfer bond (positive ion)

Quantity Value Units Method Reference Comment
Δr59.8kJ/molPHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr110.J/mol*KN/AMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
26.300.PHPMSMeot-Ner (Mautner), Hamlet, et al., 1978gas phase; Entropy change calculated or estimated; M

Chlorine anion + Benzene, 1,3-dimethyl- = (Chlorine anion • Benzene, 1,3-dimethyl-)

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

Quantity Value Units Method Reference Comment
Δr16.3kJ/molTDEqFrench, Ikuta, et al., 1982gas phase; B

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
18.300.PHPMSFrench, Ikuta, et al., 1982gas phase; M

References

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

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]

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), 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]

Caldwell and Bartmess
Caldwell, G.; Bartmess, J.E., , Unpublished results. [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]


Notes

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