Cyclopentane, 1,2-dimethyl-, cis-
- 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+
- IUPAC Standard InChIKey: RIRARCHMRDHZAR-KNVOCYPGSA-N
- CAS Registry Number: 1192-18-3
- 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: cis-1,2-Dimethylcyclopentane; 1,cis-2-Dimethylcyclopentane; 1,2-Dimethyl- cis-cyclopentane; 1,2-Dimethylcyclopentane, cis; 1-c-2-Dimethylcyclopentane; c-1,2-Dimethylcyclopentane
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Gas phase thermochemistry data
Go To: Top, Gas phase ion energetics data, IR Spectrum, 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 | -129.5 ± 1.3 | kJ/mol | Cm | Johnson, Prosen, et al., 1949 | ALS |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas | 366.14 | J/mol*K | N/A | Stull D.R., 1969 | This value was obtained using low temperature data of [ Gross M.E., 1953].; GT |
Constant pressure heat capacity of gas
| Cp,gas (J/mol*K) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 44.72 | 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 |
| 61.67 | 100. | ||
| 76.71 | 150. | ||
| 92.68 | 200. | ||
| 122.5 | 273.15 | ||
| 134.1 | 298.15 | ||
| 135.0 | 300. | ||
| 182.4 | 400. | ||
| 225.2 | 500. | ||
| 261.0 | 600. | ||
| 290.8 | 700. | ||
| 315.9 | 800. | ||
| 337.3 | 900. | ||
| 355.6 | 1000. | ||
| 371.3 | 1100. | ||
| 384.8 | 1200. | ||
| 396.4 | 1300. | ||
| 406.5 | 1400. | ||
| 415.2 | 1500. | ||
| 432.5 | 1750. | ||
| 445.0 | 2000. | ||
| 454.2 | 2250. | ||
| 461.1 | 2500. | ||
| 466.5 | 2750. | ||
| 470.7 | 3000. |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, IR Spectrum, 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: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
Ionization energy determinations
| IE (eV) | Method | Reference |
|---|---|---|
| 9.92 ± 0.05 | EI | Herzschuh and Sicker, 1981 |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| C5H11+ | 10.47 ± 0.05 | C2H5 | EI | Herzschuh and Sicker, 1981 | |
| C6H11+ | 10.57 ± 0.05 | CH3 | EI | Herzschuh and Sicker, 1981 |
IR Spectrum
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References, Notes
Data compiled by: Coblentz Society, Inc.
- GAS (30 mmHg, N2 ADDED, TOTAL PRESSURE 600 mmHg); DOW KBr FOREPRISM-GRATING; DIGITIZED BY COBLENTZ SOCIETY (BATCH II) FROM HARD COPY; 2 cm-1 resolution
- SOLUTION (10% IN CCl4 FOR 3800-1330, 10% IN CS2 FOR 1330-400 CM-1); BECKMAN IR-9 (GRATING); DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm-1 resolution
Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director
References
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, 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]
Stull D.R., 1969
Stull D.R., Jr.,
The Chemical Thermodynamics of Organic Compounds. Wiley, New York, 1969. [all data]
Gross M.E., 1953
Gross M.E.,
Low-temperature thermal data for some C7H14 alkylcyclopentanes,
J. Am. Chem. Soc., 1953, 75, 2801-2804. [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]
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, Gas phase ion energetics data, IR Spectrum, References
- Symbols used in this document:
AE Appearance energy Cp,gas Constant pressure heat capacity of gas S°gas Entropy of gas at standard conditions ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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