1,3-Cyclopentadiene
- Formula: C5H6
- Molecular weight: 66.1011
- IUPAC Standard InChI: InChI=1S/C5H6/c1-2-4-5-3-1/h1-4H,5H2
- IUPAC Standard InChIKey: ZSWFCLXCOIISFI-UHFFFAOYSA-N
- CAS Registry Number: 542-92-7
- 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) - Other names: Cyclopentadiene; Pentole; Pyropentylene; R-Pentine
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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 |
|---|---|---|---|---|---|
| ΔfH°gas | 139. | kJ/mol | Chyd | Roth, Adamczak, et al., 1991 | ALS |
| ΔfH°gas | 133.4 | kJ/mol | Eqk | Furuyama, Golden, et al., 1970 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°gas | -2960. ± 30. | kJ/mol | Ccb | Wassermann, 1935 | Corresponding ΔfHºgas = 130. kJ/mol (simple calculation by NIST; no Washburn corrections); ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas | 274.47 | J/mol*K | N/A | Furuyama S., 1970 | This a second law entropy value was obtained from study of gas-phase equilibrium. The value of S(298.2 K)=270.3(4.2) J/mol*K was obtained from other equilibrium study [ Grant C.J., 1969].; GT |
Constant pressure heat capacity of gas
| Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 33.29 | 50. | Dorofeeva O.V., 1986 | Recommended S(T) values differ from other statistically calculated values [ Turnbull A.G., 1967, Furuyama S., 1970] up to 2.6 J/mol*K. Discrepancies in Cp(T) values amount to 1.3-4.3 J/mol*K. There is an excellent agreement between selected values of S(T) and Cp(T) and those obtained by ab initio calculation [ Karni M., 1991].; GT |
| 35.04 | 100. | ||
| 40.32 | 150. | ||
| 49.53 | 200. | ||
| 68.30 | 273.15 | ||
| 75.4 ± 2.0 | 298.15 | ||
| 75.89 | 300. | ||
| 103.30 | 400. | ||
| 126.45 | 500. | ||
| 145.03 | 600. | ||
| 160.04 | 700. | ||
| 172.41 | 800. | ||
| 182.77 | 900. | ||
| 191.55 | 1000. | ||
| 199.04 | 1100. | ||
| 205.47 | 1200. | ||
| 211.00 | 1300. | ||
| 215.77 | 1400. | ||
| 219.92 | 1500. |
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:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
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
+
= (
•
)
By formula: C5H5- + C5H6 = (C5H5- • C5H6)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | <36.0 | kJ/mol | IMRB | Meot-ner, 1988 | gas phase; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 84. | J/mol*K | N/A | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | <11. ± 4.2 | kJ/mol | IMRB | Meot-ner, 1988 | gas phase; B |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 15. | 250. | PHPMS | Meot-ner, 1988 | gas phase; Entropy change calculated or estimated, DG<, ΔrH<; M |
+
= (
•
)
By formula: Cl- + C5H6 = (Cl- • C5H6)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrG° | <10.5 | kJ/mol | TDEq | French, Ikuta, et al., 1982 | gas phase; B |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 10. | 300. | PHPMS | French, Ikuta, et al., 1982 | gas phase; DG<; M |
References
Go To: Top, Gas phase thermochemistry data, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
Furuyama, Golden, et al., 1970
Furuyama, S.; Golden, D.M.; Benson, S.W.,
Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria,
J. Chem. Thermodyn., 1970, 2, 161-169. [all data]
Wassermann, 1935
Wassermann, A.,
The mechanism of additions to double bonds. Part I. Thermochemistry and kinetics of a diene synthesis,
J. Chem. Soc., 1935, 828-838. [all data]
Furuyama S., 1970
Furuyama S.,
Thermochemistry of cyclopentene and cyclopentadiene from studies of gas-phase equilibria,
J. Chem. Thermodyn., 1970, 2, 161-169. [all data]
Grant C.J., 1969
Grant C.J.,
Reversibility in the gas-phase decomposition of cyclopentene. The entropy of cyclopentadiene,
J. Chem. Soc. Chem. Comm., 1969, 667-668. [all data]
Dorofeeva O.V., 1986
Dorofeeva O.V.,
Thermodynamic properties of twenty-one monocyclic hydrocarbons,
J. Phys. Chem. Ref. Data, 1986, 15, 437-464. [all data]
Turnbull A.G., 1967
Turnbull A.G.,
Thermochemistry of biscyclopentadienyl metal compounds,
Austral. J. Chem., 1967, 20, 2059-2067. [all data]
Karni M., 1991
Karni M.,
Ab initio calculations and ideal gas thermodynamic functions of cyclopentadiene and cyclopentadiene derivatives,
J. Phys. Chem. Ref. Data, 1991, 20, 665-683. [all data]
Meot-ner, 1988
Meot-ner, M.,
The Ionic Hydrogen Bond and Solvation. 7. Interaction Energies of Carbanions with Solvent Molecules,
J. Am. Chem. Soc., 1988, 110, 12, 3858, https://doi.org/10.1021/ja00220a022
. [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
Go To: Top, Gas phase thermochemistry data, Ion clustering data, References
- Symbols used in this document:
Cp,gas Constant pressure heat capacity of gas S°gas Entropy of gas at standard conditions T Temperature ΔcH°gas Enthalpy of combustion of gas at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔrS° Entropy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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