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Disiloxane, hexamethyl-

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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: Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
liquid103.7cal/mol*KN/ADzhafarov and Kuliev, 1986 
liquid103.69cal/mol*KN/AScott, Messerly, et al., 1961 

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
74.43298.15Dzhafarov and Kuliev, 1986T = 4 to 300 K. Cp(liq) = 275.5 - 34.48x10-2T + 21.7x10-1T2 (204 to 375 K).
74.419298.15Scott, Messerly, et al., 1961T = 12 to 371 K.

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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Quantity Value Units Method Reference Comment
Tboil373. ± 2.KAVGN/AAverage of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Ttriple204.93KN/AScott, Messerly, et al., 1961, 2Uncertainty assigned by TRC = 0.02 K; TRC
Quantity Value Units Method Reference Comment
Tc518.7KN/AMcLure and Dickinson, 1976Uncertainty assigned by TRC = 0.51 K; TRC
Quantity Value Units Method Reference Comment
Pc19.00atmN/AMcLure and Dickinson, 1976Uncertainty assigned by TRC = 0.099 atm; for sample see E.Dickinson and I.A.McClure, 1974-234; TRC

Enthalpy of vaporization

DeltavapH (kcal/mol) Temperature (K) Method Reference Comment
8.82315.EBFlaningam, 1986Based on data from 300. - 383. K.; AC
7.91327.N/ADitsent, Skorokhodov, et al., 1971Based on data from 293. - 361. K.; AC
8.6324.EBScott, Messerly, et al., 1961Based on data from 309. - 411. K.; AC
8.27 ± 0.02332.CScott, Messerly, et al., 1961AC
7.91 ± 0.02351.CScott, Messerly, et al., 1961AC
7.48 ± 0.02373.CScott, Messerly, et al., 1961AC

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
309.4 - 411.563.896281203.916-64.673Scott, Messerly, et al., 1961Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kcal/mol) Temperature (K) Reference Comment
2.8489204.93Dzhafarov and Kuliev, 1986DH
2.84940204.93Scott, Messerly, et al., 1961DH
2.849204.9Domalski and Hearing, 1996AC

Entropy of fusion

DeltafusS (cal/mol*K) Temperature (K) Reference Comment
13.91204.93Scott, Messerly, et al., 1961DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Quantity Value Units Method Reference Comment
Proton affinity (review)202.3kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity195.1kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.6 ± 1.0EISeefeldt, Moller, et al., 1985LBLHLM
9.64 ± 0.01PIMolder, Pikver, et al., 1983LBLHLM
9.59 ± 0.04EIHess, Lampe, et al., 1965RDSH
9.88PEStarzewski, Dieck, et al., 1974Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C3H9SiO+21.8 ± 0.2?EIBorossay, Csakvari, et al., 1971LLK
C3H9Si+15.4 ± 0.2?EIBorossay, Csakvari, et al., 1971LLK
C3H9Si+15.36 ± 0.13?EIHess, Lampe, et al., 1965RDSH
C5H15OSi2+10.4 ± 0.2CH3EISeefeldt, Moller, et al., 1985LBLHLM
C5H15OSi2+10.20 ± 0.07CH3EIHess, Lampe, et al., 1965RDSH

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

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


Mass spectrum (electron ionization)

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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

Spectrum

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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin D.HENNEBERG, MAX-PLANCK INSTITUTE, MULHEIM, WEST GERMANY
NIST MS number 61595

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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

Kovats' RI, non-polar column, isothermal

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Column type Active phase Temperature (C) I Reference Comment
PackedC78, Branched paraffin130.597.4Dallos, Sisak, et al., 2000He; Column length: 3.3 m
PackedC78, Branched paraffin130.597.4Reddy, Dutoit, et al., 1992Chromosorb G HP; Column length: 3.3 m
PackedApolane130.598.Dutoit, 1991Column length: 3.7 m

Normal alkane RI, non-polar column, temperature ramp

View large format table.

Column type Active phase I Reference Comment
CapillarySqualane645.Szekely, Nefedov, et al., 1967Nitrogen, 5. K/min; Column length: 50. m; Column diameter: 0.25 mm; Tstart: 60. C; Tend: 250. C

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

View large format table.

Column type Active phase I Reference Comment
CapillarySqualane646.Szekely, Nefedov, et al., 1967Nitrogen; Column length: 50. m; Column diameter: 0.25 mm; Program: not specified

References

Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, NIST Free Links, Notes

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

Dzhafarov and Kuliev, 1986
Dzhafarov, O.I.; Kuliev, A.M., Heat capacity and thermodynamic properties of disiloxanes, Dokl. Akad. Nauk. Azerb., 1986, SSR 42, 56-59. [all data]

Scott, Messerly, et al., 1961
Scott, D.W.; Messerly, J.F.; Todd, S.S.; Guthrie, G.B.; Hossenlopp, I.A.; Moore, R.T.; Osborn, A.; Berg, W.T.; McCullough, J.P., Hexamethyldisiloxane: chemical thermodynamic properties and internal rotation about the siloxane linkage, J. Phys. Chem., 1961, 65, 1320-1326. [all data]

Scott, Messerly, et al., 1961, 2
Scott, D.W.; Messerly, J.F.; Todd, S.S.; Guthrie, G.B.; Hossenlopp, I.A.; Moore, R.T.; Osborn, A.G.; Berg, W.T.; McCullough, J.P., Hexamethyldisiloxane: chemical thermodynamic properties and internal rotation about the siloxane linkage, J. Phys. Chem., 1961, 65, 1320-6. [all data]

McLure and Dickinson, 1976
McLure, I.A.; Dickinson, E., Vapor pressure of hexamethyldisiloxane near its critical point: corresponding-states principle for dimethylsiloxanes, J. Chem. Thermodyn., 1976, 8, 93-5. [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]

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]

Seefeldt, Moller, et al., 1985
Seefeldt, R.; Moller, W.; Schmidt, M., Zur elektronenstossionisierung des hexamethyldisiloxans (HMDS), Z. Phys. Chem. (Leipzig), 1985, 266, 797. [all data]

Molder, Pikver, et al., 1983
Molder, U.H.; Pikver, R.J.; Koppel, I.A., Photoelectron spectra of molecules. 2. Ethers, Org. React. (N.Y. Engl. Transl.), 1983, 20, 208. [all data]

Hess, Lampe, et al., 1965
Hess, G.G.; Lampe, F.W.; Sommer, L.H., An electron impact study of ionization and dissociation of trimethylsilanes, J. Am. Chem. Soc., 1965, 87, 5327. [all data]

Starzewski, Dieck, et al., 1974
Starzewski, K.A.O.; Dieck, H.T.; Bock, H., Photoelectron spectra molecular properties. XXIII. Photoelectron spectra of silicon-substituted ylidic systems, J. Organomet. Chem., 1974, 65, 311. [all data]

Borossay, Csakvari, et al., 1971
Borossay, J.; Csakvari, B.; Szepes, L., Determination of bond energies of organic silicon compounds on the basis of appearance potentials, Int. J. Mass Spectrom. Ion Phys., 1971, 7, 47. [all data]

Dallos, Sisak, et al., 2000
Dallos, A.; Sisak, A.; Kulcsár, Z.; Kováts, E., Pair-wise interactions by gas chromatography VII. Interaction free enthalpies of solutes with secondary alcohol groups, J. Chromatogr. A, 2000, 904, 2, 211-242, https://doi.org/10.1016/S0021-9673(00)00908-0 . [all data]

Reddy, Dutoit, et al., 1992
Reddy, K.S.; Dutoit, J.-Cl.; Kovats, E. sz., Pair-wise interactions by gas chromatography. I. Interaction free enthalpies of solutes with non-associated primary alcohol groups, J. Chromatogr., 1992, 609, 1-2, 229-259, https://doi.org/10.1016/0021-9673(92)80167-S . [all data]

Dutoit, 1991
Dutoit, J., Gas chromatographic retention behaviour of some solutes on structurally similar polar and non-polar stationary phases, J. Chromatogr., 1991, 555, 1-2, 191-204, https://doi.org/10.1016/S0021-9673(01)87179-X . [all data]

Szekely, Nefedov, et al., 1967
Szekely, T.; Nefedov, O.M.; Garzo, G.; Shiryayav, V.I.; Fritz, D., Gas chromatographic investigation of the thermal decomposition of polydimethylsilylene, Acta Chim. Acad. Sci. Hung., 1967, 54, 3-4, 241-254. [all data]


Notes

Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, NIST Free Links, References