1,4-Cyclohexadiene
- Formula: C6H8
- Molecular weight: 80.1277
- IUPAC Standard InChIKey: UVJHQYIOXKWHFD-UHFFFAOYSA-N
- CAS Registry Number: 628-41-1
- 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. - Other names: 1,4-Dihydrobenzene; Cyclohexa-1,4-diene
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Phase change data
Go To: Top, 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 as indicated in comments:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DRB - Donald R. Burgess, Jr.
AC - William E. Acree, Jr., James S. Chickos
CAL - James S. Chickos, William E. Acree, Jr., Joel F. Liebman, Students of Chem 202 (Introduction to the Literature of Chemistry), University of Missouri -- St. Louis
DH - Eugene S. Domalski and Elizabeth D. Hearing
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Tboil | 354.7 | K | N/A | Aldrich Chemical Company Inc., 1990 | BS |
Tboil | 362.70 | K | N/A | Anonymous, 1962 | Uncertainty assigned by TRC = 0.2 K; TRC |
Tboil | 362.55 | K | N/A | Anonymous, 1942 | Uncertainty assigned by TRC = 0.3 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 222.83 | K | N/A | Anonymous, 1942 | Uncertainty assigned by TRC = 0.2 K; TRC |
Tfus | 351. | K | N/A | White and Bishop, 1940 | Crystal phase 1 phase; Uncertainty assigned by TRC = 4. K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 224.0 | K | N/A | Geipel and Wolf, 1976 | Crystal phase 1 phase; Uncertainty assigned by TRC = 0.2 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 34.3 | kJ/mol | V | Luk'yanova, Timofeeva, et al., 1991 | ALS |
ΔvapH° | 34.3 | kJ/mol | N/A | Luk'yanova, Timofeeva, et al., 1991 | DRB |
ΔvapH° | 35.05 ± 0.04 | kJ/mol | V | Steele, Chirico, et al., 1989 | ALS |
ΔvapH° | 35.1 | kJ/mol | N/A | Steele, Chirico, et al., 1989 | DRB |
Enthalpy of vaporization
ΔvapH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
34.0 | 319. | A | Stephenson and Malanowski, 1987 | Based on data from 304. to 360. K.; AC |
33.9 | 308. | MM | Letcher and Marsicano, 1974 | Based on data from 304. to 322. K.; AC |
Enthalpy of fusion
ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
5.72 | 224. | Domalski and Hearing, 1996 | AC |
Entropy of fusion
ΔfusS (J/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
4.25 | 192. | Domalski and Hearing, 1996 | CAL |
25.51 | 224. |
Enthalpy of phase transition
ΔHtrs (kJ/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.816 | 192.0 | crystaline, II | crystaline, I | Geipel and Wolf, 1976, 2 | DH |
5.7153 | 224.0 | crystaline, I | liquid | Geipel and Wolf, 1976, 2 | DH |
Entropy of phase transition
ΔStrs (J/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
4.25 | 192.0 | crystaline, II | crystaline, I | Geipel and Wolf, 1976, 2 | DH |
25.51 | 224.0 | crystaline, I | liquid | Geipel and Wolf, 1976, 2 | DH |
Reaction thermochemistry 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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
By formula: 2H2 + C6H8 = C6H12
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -233. | kJ/mol | Chyd | Roth, Adamczak, et al., 1991 | liquid phase |
ΔrH° | -225.5 ± 1.4 | kJ/mol | Chyd | Turner, Mallon, et al., 1973 | liquid phase; solvent: Glacial acetic acid |
By formula: C6H8 = C6H8
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | -1.6 ± 0.8 | kJ/mol | Eqk | Taskinen and Nummelin, 1986 | liquid phase; solvent: (CH3)2SO; GLC |
Gas phase ion energetics data
Go To: Top, Phase change data, Reaction 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
Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
View reactions leading to C6H8+ (ion structure unspecified)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
Proton affinity (review) | 837. | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 808.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
8.82 | PE | Kimura, Katsumata, et al., 1981 | LLK |
8.82 ± 0.02 | PE | Bieri, Burger, et al., 1977 | LLK |
8.82 ± 0.02 | PI | Demeo and El-Sayed, 1970 | RDSH |
8.65 ± 0.05 | EI | Franklin and Carroll, 1969 | RDSH |
8.80 | PE | Bischof, Hashmall, et al., 1969 | RDSH |
8.82 | PE | Kimura, Katsumata, et al., 1981 | Vertical value; LLK |
8.82 | PE | Bock and Kaim, 1980 | Vertical value; LLK |
8.80 | PE | Kobayashi, 1978 | Vertical value; LLK |
8.82 | PE | Heilbronner, Brogli, et al., 1976 | Vertical value; LLK |
Appearance energy determinations
Ion | AE (eV) | Other Products | Method | Reference | Comment |
---|---|---|---|---|---|
C3H2+ | 19.21 ± 0.15 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C3H3+ | 15.20 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C3H4+ | 13.95 ± 0.10 | ? | EI | Franklin and Carroll, 1969 | RDSH |
C4H2+ | 17.82 ± 0.25 | C2H2+2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H3+ | 17.08 ± 0.10 | C2H2+H2+H? | EI | Franklin and Carroll, 1969 | RDSH |
C4H4+ | 13.55 ± 0.10 | C2H2+H2 | EI | Franklin and Carroll, 1969 | RDSH |
C4H5+ | 14.48 ± 0.10 | C2H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C4H6+ | 12.17 ± 0.10 | C2H2 | EI | Franklin and Carroll, 1969 | RDSH |
C5H3+ | 16.12 ± 0.10 | CH3+H2? | EI | Franklin and Carroll, 1969 | RDSH |
C5H5+ | 13.41 ± 0.10 | CH3 | EI | Franklin and Carroll, 1969 | RDSH |
C5H5+ | 13.6 | CH3 | EI | Harrison, Haynes, et al., 1965 | RDSH |
C6H5+ | 13.92 ± 0.10 | H2+H | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 9.61 ± 0.10 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C6H6+ | 9.86 ± 0.05 | H2 | EI | Franklin and Carroll, 1969 | RDSH |
C6H7+ | 10.55 | H | PIPECO | Lias and Ausloos, 1985 | LBLHLM |
C6H7+ | 10.94 ± 0.10 | H | EI | Franklin and Carroll, 1969 | RDSH |
References
Go To: Top, Phase change data, Reaction 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.
Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc.,
Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]
Anonymous, 1962
Anonymous, R.,
, Am. Pet. Inst. Res. Proj. 58A, Annu. Rep., 1962. [all data]
Anonymous, 1942
Anonymous, R.,
, Am. Pet. Inst. Res. Proj. 6, Natl. Bur. Stand., 1942. [all data]
White and Bishop, 1940
White, A.H.; Bishop, W.S.,
Dielectric Evidence of Molecular Rotation in the Crystals of Certain Non-aromatic Compounds,
J. Am. Chem. Soc., 1940, 62, 8-16. [all data]
Geipel and Wolf, 1976
Geipel, G.; Wolf, G.,
Molar Heat Capacity of Cyclohexadiene(1,4) and Cyclohexadiene(1,3) in Temperature Range of 10... 300K,
Z. Phys. Chem. (Leipzig), 1976, 257, 587. [all data]
Luk'yanova, Timofeeva, et al., 1991
Luk'yanova, V.A.; Timofeeva, L.P.; Kozina, M.P.; Kirin, V.N.; Tarakanova, A.V.,
Enthalpies of formation of certain unsaturated cyclic hydrocarbons,
Russ. J. Phys. Chem. (Engl. Transl.), 1991, 65, 439-441. [all data]
Steele, Chirico, et al., 1989
Steele, W.V.; Chirico, R.D.; Nguyen, A.; Hossenlopp, I.A.; Smith, N.K.,
Determination of some pure compound ideal-gas enthalpies of formation,
AIChE Symp. Ser., 1989, 85, 140-162. [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]
Letcher and Marsicano, 1974
Letcher, T.M.; Marsicano, F.,
Vapour pressures and densities of some unsaturated C6 acyclic and cyclic hydrocarbons between 300 and 320 K,
The Journal of Chemical Thermodynamics, 1974, 6, 5, 509-514, https://doi.org/10.1016/0021-9614(74)90013-5
. [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]
Geipel and Wolf, 1976, 2
Geipel, G.; Wolf, G.,
Die molare Wärmekapazität von Cyclohexadien(1,4) und Cyclohexadien(1,3) im Temperaturegebiet von 10...300K,
Z. Phys. Chem., 1976, 257, 587-593. [all data]
Roth, Adamczak, et al., 1991
Roth, W.R.; Adamczak, O.; Breuckmann, R.; Lennartz, H.-W.; Boese, R.,
Die Berechnung von Resonanzenergien; das MM2ERW-Kraftfeld,
Chem. Ber., 1991, 124, 2499-2521. [all data]
Turner, Mallon, et al., 1973
Turner, R.B.; Mallon, B.J.; Tichy, M.; Doering, W.v.E.; Roth, W.R.; Schroder, G.,
Heats of hydrogenation. X. Conjugative interaction in cyclic dienes and trienes,
J. Am. Chem. Soc., 1973, 95, 8605-8610. [all data]
Taskinen and Nummelin, 1986
Taskinen, E.; Nummelin, K.,
Thermodynamics of vinyl ethers. 31. Isomer equilibria in some six- and seven-membered cyclic dienes,
J. Org. Chem., 1986, 50, 4844-4847. [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]
Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S.,
Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules
in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]
Bieri, Burger, et al., 1977
Bieri, G.; Burger, F.; Heilbronner, E.; Maier, J.P.,
Valence ionization enrgies of hydrocarbons,
Helv. Chim. Acta, 1977, 60, 2213. [all data]
Demeo and El-Sayed, 1970
Demeo, D.A.; El-Sayed, M.A.,
Ionization potential and structure of olefins,
J. Chem. Phys., 1970, 52, 2622. [all data]
Franklin and Carroll, 1969
Franklin, J.L.; Carroll, S.R.,
Effect of molecular structure on ionic decomposition. II. An electron-impact study of 1,3-and 1,4-cyclohexadiene and 1,3,5-hexatriene,
J. Am. Chem. Soc., 1969, 91, 6564. [all data]
Bischof, Hashmall, et al., 1969
Bischof, P.; Hashmall, J.A.; Heilbronner, E.; Hornung, V.,
Photoelektronspektroskopische Bestimmung der Wechselwirkung zwischen nichtkonjugierten Doppelbindungen,
Helv. Chim. Acta, 1969, 52, 1745. [all data]
Bock and Kaim, 1980
Bock, H.; Kaim, W.,
Radical ions. 37. Ionization and one-electron oxidation of electron-rich silylalkyl olefins,
J. Am. Chem. Soc., 1980, 102, 4429. [all data]
Kobayashi, 1978
Kobayashi, T.,
A new rule for photoelectron angular distributions of molecules,
Phys. Lett. A, 1978, 69, 31. [all data]
Heilbronner, Brogli, et al., 1976
Heilbronner, E.; Brogli, F.; Vogel, E.,
Photoelectron spectroscopic assignment of symmetry to the ground state and first excited state of the 1,4-cyclohexadiene radical cation,
J. Electron Spectrosc. Relat. Phenom., 1976, 9, 227. [all data]
Harrison, Haynes, et al., 1965
Harrison, A.G.; Haynes, P.; McLean, S.; Meyer, F.,
The mass spectra of methyl-substituted cyclopentadienes,
J. Am. Chem. Soc., 1965, 87, 5099. [all data]
Lias and Ausloos, 1985
Lias, S.G.; Ausloos, P.,
Structures of C6H7+ ions formed in unimolecular and bimolecular reactions,
J. Chem. Phys., 1985, 82, 3613. [all data]
Notes
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy Tboil Boiling point Tfus Fusion (melting) point Ttriple Triple point temperature ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔfusH Enthalpy of fusion ΔfusS Entropy of fusion ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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