Cyclopentane, 1,2-dimethyl-, trans-
- Formula: C7H14
- Molecular weight: 98.1861
- IUPAC Standard InChI: InChI=1S/C7H14/c1-6-4-3-5-7(6)2/h6-7H,3-5H2,1-2H3/t6-,7-/m0/s1
- IUPAC Standard InChIKey: RIRARCHMRDHZAR-BQBZGAKWSA-N
- CAS Registry Number: 822-50-4
- 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. - Stereoisomers:
- Other names: trans-1,2-Dimethylcyclopentane; 1,trans-2-Dimethylcyclopentane; 1,2-Dimethylcyclopentane, trans; t-1,2-Dimethylcyclopentane; (E)-1,2-Dimethylcyclopentane; Cyclopentane, 1,2-dimethyl-
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry 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 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 | -136.7 ± 1.3 | kJ/mol | Cm | Johnson, Prosen, et al., 1949 | ALS |
Constant pressure heat capacity of gas
| Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 44.51 | 50. | Thermodynamics Research Center, 1997 | p=1 bar. Recommended values are in close agreement with those calculated by a method of increments [ Epstein M.B., 1949] at low temperatures. Discrepancies increase up to 2-4 J/mol*K at T=1500 K.; GT |
| 61.44 | 100. | ||
| 76.91 | 150. | ||
| 93.09 | 200. | ||
| 122.9 | 273.15 | ||
| 134.5 | 298.15 | ||
| 135.4 | 300. | ||
| 182.7 | 400. | ||
| 225.4 | 500. | ||
| 261.1 | 600. | ||
| 290.9 | 700. | ||
| 316.0 | 800. | ||
| 337.4 | 900. | ||
| 355.6 | 1000. | ||
| 371.3 | 1100. | ||
| 384.8 | 1200. | ||
| 396.5 | 1300. | ||
| 406.5 | 1400. | ||
| 415.3 | 1500. | ||
| 432.5 | 1750. | ||
| 445.0 | 2000. | ||
| 454.2 | 2250. | ||
| 461.1 | 2500. | ||
| 466.5 | 2750. | ||
| 470.7 | 3000. |
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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°liquid | -171.3 ± 1.2 | kJ/mol | Cm | Johnson, Prosen, et al., 1949 | |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°liquid | -4584.2 ± 1.1 | kJ/mol | Cm | Johnson, Prosen, et al., 1949 | Corresponding ΔfHºliquid = -171.2 kJ/mol (simple calculation by NIST; no Washburn corrections) |
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 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
2 + 2
=
+
By formula: 2H2 + 2C7H12 = C7H14 + C7H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -94.35 ± 0.75 | kJ/mol | Chyd | Allinger, Dodziuk, et al., 1982 | liquid phase; solvent: Hexane |
2 +
=
By formula: 2H2 + C7H10 = C7H14
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | -231. ± 0.8 | kJ/mol | Chyd | Roth, Adamczak, et al., 1991 | liquid phase |
Gas phase ion energetics 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:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 9.48 ± 0.05 | EI | Holmes and Lossing, 1991 | LL |
| 9.95 ± 0.05 | EI | Herzschuh and Sicker, 1981 | LLK |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| C5H9+ | 10.80 ± 0.05 | C2H5 | EI | Herzschuh and Sicker, 1981 | LLK |
| C6H11+ | 10.70 ± 0.05 | CH3 | EI | Herzschuh and Sicker, 1981 | LLK |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry 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.
Johnson, Prosen, et al., 1949
Johnson, W.H.; Prosen, E.J.; Rossini, F.D.,
Heats of combustion and isomerization of the six C7H14 alkylcyclopentanes,
J. Res. NBS, 1949, 42, 251-255. [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]
Epstein M.B., 1949
Epstein M.B.,
Heats, equilibrium constants, and free energies of formation of the dimethylcyclopentanes,
J. Res. Nat. Bur. Stand., 1949, 43, 245-250. [all data]
Allinger, Dodziuk, et al., 1982
Allinger, N.L.; Dodziuk, H.; Rogers, D.W.; Naik, S.N.,
Heats of hydrogenation and formation of some 5-membered ring compounds by molecular mechanics calculations and direct measurements,
Tetrahedron, 1982, 38, 1593-1597. [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]
Holmes and Lossing, 1991
Holmes, J.L.; Lossing, F.P.,
Ionization energies of homologous organic compounds and correlation with molecular size,
Org. Mass Spectrom., 1991, 26, 537. [all data]
Herzschuh and Sicker, 1981
Herzschuh, R.; Sicker, A.,
Stereochemische einflusse auf die ionisations- und auftrittsenergien cis/trans-isomerer dimethylcycloalkane,
Z. Chem., 1981, 21, 409. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
AE Appearance energy Cp,gas Constant pressure heat capacity of gas ΔcH°liquid Enthalpy of combustion of liquid at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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