Cyclotetrasiloxane, octamethyl-

• Formula: C₈H₂₄O₄Si₄
• Molecular weight: 296.6158
• IUPAC Standard InChI: InChI=1S/C8H24O4Si4/c1-13(2)9-14(3,4)11-16(7,8)12-15(5,6)10-13/h1-8H3 Copy

  
• IUPAC Standard InChIKey: HMMGMWAXVFQUOA-UHFFFAOYSA-N Copy
• CAS Registry Number: 556-67-2
• 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: Oktamethylcyklotetrasiloxan; NUC Silicone VS 7207; CO9810; O9810; Octamethyltetrasiloxane; Octamethylcyclotetrasiloxane; Cyclotetrasilane, octamethyl
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• Information on this page:
  • Phase change data
  • Gas Chromatography
  • References
  • Notes
• Other data available:
  • IR Spectrum
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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Phase change 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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Enthalpy of fusion

Gas Chromatography

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Van Den Dool and Kratz RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, temperature ramp

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Normal alkane RI, non-polar column, custom temperature program

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References

Go To: Top, Phase change data, Gas Chromatography, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

PCR Inc., 1990
PCR Inc., Research Chemicals Catalog 1990-1991, PCR Inc., Gainesville, FL, 1990, 1. [all data]

Myers and Clever, 1969
Myers, R.S.; Clever, H.L., Surface Tension of Octamethylcyclotetrasiloxane and Hexamethyldisilazane and Their Solutions with Carbon Tetrachloride and n-Hexadecane, J. Chem. Eng. Data, 1969, 14, 161-164. [all data]

Alvik and Dale, 1971
Alvik, T.; Dale, J., On the Lack of Conformational Preferences for Cyclic Dimethylsiloxane Oligomers., Acta Chem. Scand., 1971, 25, 2131, https://doi.org/10.3891/acta.chem.scand.25-2131 . [all data]

Marsh, 1968
Marsh, K.N., Thermodynamics of Octamethylcyclotetrasiloxane mixtures, Trans. Faraday Soc., 1968, 64, 883. [all data]

Osthoff, Grubb, et al., 1953
Osthoff, R.C.; Grubb, W.T.; Burkhard, C.A., Physical Properties of organosilicon compounds. I. Hexamethylcyclotrisiloxane and Octamethylcyclotetrasiloxane, J. Am. Chem. Soc., 1953, 75, 2227-9. [all data]

Mekhtiev and Karasharli, 1981
Mekhtiev, S.A.; Karasharli, K.A., Analysis of the results of thermodynamic studies of a series of organosilicon compounds, Azerb. Khim. Zhur., 1981, (5), 85-88. [all data]

McLure and Neville, 1982
McLure, I.A.; Neville, J.F., The critical temperatures and pressures of hexamethyldisilmethylene, octamethylcyclotetrasiloxane, and decamethylcyclpentasiloxane, J. Chem. Thermodyn., 1982, 14, 385-8. [all data]

Young, 1972
Young, C.L., Equilibrium properties of octamethylcyclotetrasiloxane near its critical point and applicability of the principle of corresponding states, J. Chem. Thermodyn., 1972, 4, 65. [all data]

Voronkov, Klyuchnikov, et al., 1991
Voronkov, M.G.; Klyuchnikov, V.A.; Mironenko, E.V.; Shvets, G.N.; Danilova, T.F.; Khudobin, Yu.I., Thermochemistry of organosilicon compounds, Journal of Organometallic Chemistry, 1991, 406, 1-2, 91-97, https://doi.org/10.1016/0022-328X(91)83174-3 . [all data]

Osthoff and Grubb, 1954
Osthoff, Robert C.; Grubb, W.T., Physical Properties of Organosilicon Compounds. III. Thermodynamic Properties of Octamethylcyclotetrasiloxane, J. Am. Chem. Soc., 1954, 76, 2, 399-401, https://doi.org/10.1021/ja01631a025 . [all data]

Flaningam, 1986
Flaningam, Ora L., Vapor pressures of poly(dimethylsiloxane) oligomers, J. Chem. Eng. Data, 1986, 31, 3, 266-272, https://doi.org/10.1021/je00045a002 . [all data]

Ditsent, Skorokhodov, et al., 1971
Ditsent, V.E.; Skorokhodov, I.I.; Terent'eva, N.A.; Zolotareva, M.N., Russ. J. Phys. Chem., 1971, 45, 6, 901. [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]

Mekhtiev, Karasharli, et al., 1975
Mekhtiev, S.A.; Karasharli, K.A.; Dzhafarov, O.I., The true heat capacity of 1,1,3,3,5,5-hexamethyl-7,7-diphenylcyclotetrasiloxane in the temperature range 13 to 320 K, Zhur. Fiz. Khim., 1975, 49, 259. [all data]

Alvik, Dale, et al., 1971
Alvik, Thor; Dale, Johannes; Fernholt, L.; Hedberg, Kenneth; Schaumburg, Kjeld; Ehrenberg, L., On the Lack of Conformational Preferences for Cyclic Dimethylsiloxane Oligomers., Acta Chem. Scand., 1971, 25, 2131-2141, https://doi.org/10.3891/acta.chem.scand.25-2131 . [all data]

Richmond and Pombo-Villar, 1998
Richmond, R.; Pombo-Villar, E., Short communication. Use of persistent trace gas chromatography artifacts for the calculation of pseudo-Sadtler retention indices, J. Chromatogr. A, 1998, 811, 1-2, 241-245, https://doi.org/10.1016/S0021-9673(98)00285-4 . [all data]

Jung, Wichmann, et al., 1999
Jung, A.; Wichmann, K.-H.; Kolb, M., VOC emission of polymeric packaging materials, LaborPraxis, 1999, 23, 9, 20-22. [all data]

Fujimoto, Ohtani, et al., 1990
Fujimoto, S.; Ohtani, H.; Yamagiwa, K.; Tsuge, S., Study on retention behavior of cyclic siloxanes by high resolution pyrolysis-gas chromatography with a fused silica capillary column, J. Hi. Res. Chromatogr., 1990, 13, 6, 397-404, https://doi.org/10.1002/jhrc.1240130603 . [all data]

Kazuyoshi, Seiichi, et al., 2000
Kazuyoshi, N.; Seiichi, Y.; Kazuo, K.; Katsumi, I.; Okihiko, S., Polymer analysis by improved pyrolysis gas chromatography hyphenated with four specific detectors, J. Soc. Cosmet. Chem. Jpn., 2000, 34, 2, 142-151, https://doi.org/10.5107/sccj.34.142 . [all data]

Notes

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• Symbols used in this document:
  

  Pc	Critical pressure
  Tboil	Boiling point
  Tc	Critical temperature
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  Vc	Critical volume
  ΔfusH	Enthalpy of fusion
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions
  ρc	Critical density

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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