Ethylbenzene
- Formula: C8H10
- Molecular weight: 106.1650
- IUPAC Standard InChIKey: YNQLUTRBYVCPMQ-UHFFFAOYSA-N
- CAS Registry Number: 100-41-4
- 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:
- Other names: Benzene, ethyl-; Ethylbenzol; EB; Phenylethane; Aethylbenzol; Ethylbenzeen; Etilbenzene; Etylobenzen; NCI-C56393; UN 1175; α-Methyltoluene; NSC 406903
- Permanent link for this species. Use this link for bookmarking this species for future reference.
- Information on this page:
- Other data available:
- Data at other public NIST sites:
- Options:
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.
Gas phase ion energetics data
Go To: Top, 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 8.77 ± 0.01 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 188.3 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 181.7 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Proton affinity at 298K
Proton affinity (kcal/mol) | Reference | Comment |
---|---|---|
188.8 | Aue, Guidoni, et al., 2000 | Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM |
Gas basicity at 298K
Gas basicity (review) (kcal/mol) | Reference | Comment |
---|---|---|
181.7 | Aue, Guidoni, et al., 2000 | Experimental literature data re-evaluated by the authors using ab initio protonation entropies; MM |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.77 | PE | Howell, Goncalves, et al., 1984 | LBLHLM |
8.61 | PE | Klasinc, Kovac, et al., 1983 | LBLHLM |
8.65 ± 0.10 | EI | Selim and Helal, 1982 | LBLHLM |
8.76 | EI | McLoughlin, Morrison, et al., 1979 | LLK |
8.768 ± 0.008 | EQ | Lias and Ausloos, 1978 | LLK |
8.75 ± 0.05 | PI | Akopyan and Vilesov, 1966 | RDSH |
8.76 ± 0.01 | PI | Watanabe, Nakayama, et al., 1962 | RDSH |
8.77 ± 0.01 | S | Hammond, Price, et al., 1950 | RDSH |
8.77 | PE | Howell, Goncalves, et al., 1984 | Vertical value; LBLHLM |
8.73 | PE | Klasinc, Kovac, et al., 1983 | Vertical value; LBLHLM |
9.38 | PE | Deshmukh, Dutta, et al., 1982 | Vertical value; LBLHLM |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C5H5+ | 16.2 ± 0.2 | C2H2+CH3 | EI | Tajima and Tsuchiya, 1973 | LLK |
C6H6+ | 11.0 ± 0.1 | C2H4? | PI | Akopyan and Vilesov, 1966 | RDSH |
C7H7+ | 9.9 ± 0.1 | CH3 | TRPI | Lifshitz and Malinovich, 1984 | LBLHLM |
C7H7+ | 10.15 ± 0.10 | CH3 | EI | Selim and Helal, 1982 | LBLHLM |
C7H7+ | 10.06 | CH3 | EI | McLoughlin, Morrison, et al., 1979 | LLK |
C7H7+ | 10.9 ± 0.1 | CH3 | PI | Akopyan and Vilesov, 1966 | RDSH |
C8H9+ | 10.60 | H | EI | McLoughlin, Morrison, et al., 1979 | LLK |
C8H9+ | 12.1 ± 0.1 | H | PI | Akopyan and Vilesov, 1966 | RDSH |
C8H9+ | 11.4 ± 0.1 | H | EI | Meyer, Haynes, et al., 1965 | RDSH |
De-protonation reactions
C8H9- + =
By formula: C8H9- + H+ = C8H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 406.0 ± 4.6 | kcal/mol | CIDT | Graul and Squires, 1990 | gas phase; From decarboxylation threshold. Stable form probably the spiro[2.5]octadienide Maas and van Keelen, 1989; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 397.7 ± 4.7 | kcal/mol | H-TS | Graul and Squires, 1990 | gas phase; From decarboxylation threshold. Stable form probably the spiro[2.5]octadienide Maas and van Keelen, 1989; B |
C8H9- + =
By formula: C8H9- + H+ = C8H10
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 379.7 ± 2.1 | kcal/mol | G+TS | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 373.3 ± 2.0 | kcal/mol | IMRE | Bartmess, Scott, et al., 1979 | gas phase; value altered from reference due to change in acidity scale; B |
References
Go To: Top, 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.
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]
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]
Klasinc, Kovac, et al., 1983
Klasinc, L.; Kovac, B.; Gusten, H.,
Photoelectron spectra of acenes. Electronic structure and substituent effects,
Pure Appl. Chem., 1983, 55, 289. [all data]
Selim and Helal, 1982
Selim, E.T.M.; Helal, A.I.,
The study of C1-C3 monosubstituted alkyl benzenes by the inverse convolution of first differential ionization efficiency curves,
Org. Mass Spectrom., 1982, 17, 539. [all data]
McLoughlin, Morrison, et al., 1979
McLoughlin, R.G.; Morrison, J.D.; Traeger, J.C.,
Photoionization of the C-1 - C-4 monosubstituted alkyl benzenes: Thermochemistry of [C7H7]+ and [C8H9]+ formation,
Org. Mass Spectrom., 1979, 14, 104. [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]
Akopyan and Vilesov, 1966
Akopyan, M.E.; Vilesov, F.I.,
A mass-spectrometric study of the photo-ionisation of benzene derivatives at wavelengths up to 885 A,
Zh. Fiz. Khim., 1966, 40, 125, In original 63. [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]
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]
Deshmukh, Dutta, et al., 1982
Deshmukh, P.; Dutta, T.K.; Hwang, J.L.-S.; Housecroft, C.E.; Fehlner, T.P.,
Photoelectron spectroscopic measurements of the relative charge on carbyne fragments bound to polynuclear cobalt carbonyl clusters,
J. Am. Chem. Soc., 1982, 104, 1740. [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]
Lifshitz and Malinovich, 1984
Lifshitz, C.; Malinovich, Y.,
Time resolved photoionization mass spectrometry in the millisecond range,
Int. J. Mass Spectrom. Ion Processes, 1984, 60, 99. [all data]
Meyer, Haynes, et al., 1965
Meyer, F.; Haynes, P.; McLean, S.; Harrison, A.G.,
An electron impact study of some C8H10 isomers,
Can. J. Chem., 1965, 43, 211. [all data]
Graul and Squires, 1990
Graul, S.T.; Squires, R.R.,
Gas-Phase Acidities Derived from Threshold Energies for Activated Reactions,
J. Am. Chem. Soc., 1990, 112, 7, 2517, https://doi.org/10.1021/ja00163a007
. [all data]
Maas and van Keelen, 1989
Maas, W.P.M.; van Keelen, P.A.,
On the Generation and Characterization of the Spiro[2,5]Octadienyl Anion in the Gas Phase,
Org. Mass Spectrom., 1989, 24, 8, 546, https://doi.org/10.1002/oms.1210240807
. [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]
Notes
Go To: Top, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions - 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.