Silane, tetramethyl-
- Formula: C4H12Si
- Molecular weight: 88.2236
- IUPAC Standard InChIKey: CZDYPVPMEAXLPK-UHFFFAOYSA-N
- CAS Registry Number: 75-76-3
- 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. - Other names: Tetramethylsilane; (CH3)4Si; Silicon, tetramethyl-; Tetramethylsilicane; UN 2749; Si(CH3)4; CT2050; TMS; NSC 5210; T2050
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Phase change data
Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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:
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 |
---|---|---|---|---|---|
Tboil | 299.7 | K | N/A | PCR Inc., 1990 | BS |
Tboil | 299. | K | N/A | Sommer, Goldberg, et al., 1946 | Uncertainty assigned by TRC = 3. K; ~; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Ttriple | 172. ± 5. | K | AVG | N/A | Average of 7 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tc | 448.640 | K | N/A | McGlashan and McKinnon, 1977 | Uncertainty assigned by TRC = 0.03 K; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Pc | 27.84 | atm | N/A | McGlashan and McKinnon, 1977 | Uncertainty assigned by TRC = 0.01 atm; TRC |
Quantity | Value | Units | Method | Reference | Comment |
Vc | 0.362 | l/mol | N/A | McGlashan and McKinnon, 1977 | Uncertainty assigned by TRC = 0.008 l/mol; TRC |
Quantity | Value | Units | Method | Reference | Comment |
ΔvapH° | 6.2 ± 0.1 | kcal/mol | C | Voronkov, Baryshok, et al., 1988 | AC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
5.7849 | 299.80 | N/A | Aston, Kennedy, et al., 1941 | P = 101.325 kPa; DH |
5.78 ± 0.02 | 299. | C | Bergmann and Haskelberg, 1941 | AC |
Entropy of vaporization
ΔvapS (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
19.29 | 299.80 | Aston, Kennedy, et al., 1941 | P; DH |
Antoine Equation Parameters
log10(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)
View plot Requires a JavaScript / HTML 5 canvas capable browser.
Temperature (K) | A | B | C | Reference | Comment |
---|---|---|---|---|---|
208.93 to 293.64 | 3.97132 | 1047.272 | -36.057 | Aston, Kennedy, et al., 1941 | Coefficents calculated by NIST from author's data. |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
1.61 | 174. | Domalski and Hearing, 1996 | AC |
Enthalpy of phase transition
ΔHtrs (kcal/mol) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
0.168 | 165.920 | crystaline, α | liquid | Harada, Atake, et al., 1977 | DH |
1.405 | 171.016 | crystaline, β | liquid | Harada, Atake, et al., 1977 | DH |
1.3960 | 70.983 | crystaline, II | liquid | Shinoda, Enokida, et al., 1973 | Metastable form.; DH |
1.6112 | 174.049 | crystaline, I | liquid | Shinoda, Enokida, et al., 1973 | Stable form.; DH |
1.4268 | 171.04 | crystaline, I | liquid | Aston, Kennedy, et al., 1941 | DH |
1.648 | 174.12 | crystaline, II | liquid | Aston, Kennedy, et al., 1941 | DH |
Entropy of phase transition
ΔStrs (cal/mol*K) | Temperature (K) | Initial Phase | Final Phase | Reference | Comment |
---|---|---|---|---|---|
1.01 | 165.920 | crystaline, α | liquid | Harada, Atake, et al., 1977 | DH |
8.215 | 171.016 | crystaline, β | liquid | Harada, Atake, et al., 1977 | DH |
8.164 | 70.983 | crystaline, II | liquid | Shinoda, Enokida, et al., 1973 | Metastable; DH |
9.257 | 174.049 | crystaline, I | liquid | Shinoda, Enokida, et al., 1973 | Stable; DH |
8.341 | 171.04 | crystaline, I | liquid | Aston, Kennedy, et al., 1941 | DH |
9.465 | 174.12 | crystaline, II | liquid | Aston, Kennedy, et al., 1941 | DH |
Gas phase ion energetics data
Go To: Top, Phase change data, Gas Chromatography, References, Notes
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:
L - Sharon G. Lias
Data compiled as indicated in comments:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 9.80 ± 0.04 | eV | N/A | N/A | L |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
9.80 ± 0.03 | PI | Murphy and Beauchamp, 1977 | LLK |
9.6 | PE | Potzinger, Ritter, et al., 1975 | LLK |
9.99 ± 0.03 | EI | MacLean and Sacher, 1974 | LLK |
9.79 ± 0.04 | PE | Jonas, Schweitzer, et al., 1973 | LLK |
9.4 ± 0.1 | PE | Evans, Green, et al., 1972 | LLK |
9.85 ± 0.16 | EI | Lappert, Pedley, et al., 1971 | LLK |
9.74 ± 0.05 | EI | Potzinger and Lampe, 1970 | RDSH |
9.86 ± 0.02 | PI | Distefano, 1970 | RDSH |
9.85 ± 0.16 | EI | Lappert, Simpson, et al., 1969 | RDSH |
9.9 ± 0.1 | EI | Band, Davidson, et al., 1968 | RDSH |
9.98 ± 0.03 | EI | Hess, Lampe, et al., 1965 | RDSH |
10.29 | PE | Khvostenko, Zykov, et al., 1981 | Vertical value; LLK |
10.4 | PE | Roberge, Sandorfy, et al., 1978 | Vertical value; LLK |
10.57 | PE | Starzewski, Richter, et al., 1976 | Vertical value; LLK |
Appearance energy determinations
De-protonation reactions
C4H11Si- + =
By formula: C4H11Si- + H+ = C4H12Si
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 388.2 ± 3.1 | kcal/mol | G+TS | Damrauer, Kass, et al., 1988 | gas phase; Comparable to fluorobenzene; B |
ΔrH° | 390.9 ± 2.0 | kcal/mol | D-EA | Wetzel and Brauman, 1988 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 379.0 ± 3.0 | kcal/mol | IMRB | Damrauer, Kass, et al., 1988 | gas phase; Comparable to fluorobenzene; B |
ΔrG° | 381.7 ± 2.1 | kcal/mol | H-TS | Wetzel and Brauman, 1988 | gas phase; B |
ΔrG° | 390.7 ± 5.0 | kcal/mol | IMRB | DePuy and Damrauer, 1984 | gas phase; B |
Gas Chromatography
Go To: Top, Phase change 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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | C78, Branched paraffin | 130. | 428.1 | Dallos, Sisak, et al., 2000 | He; Column length: 3.3 m |
Packed | C78, Branched paraffin | 130. | 428.0 | Reddy, Dutoit, et al., 1992 | Chromosorb G HP; Column length: 3.3 m |
Packed | Apolane | 110. | 428.4 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 130. | 427.6 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 150. | 426.8 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 170. | 425.9 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 190. | 424.8 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 210. | 423.6 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 230. | 422.4 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 30. | 430. | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 50. | 429.8 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 70. | 429.4 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 90. | 429. | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Packed | Apolane | 70. | 429.4 | Riedo, Fritz, et al., 1976 | He, Chromosorb; Column length: 2.4 m |
Capillary | Apiezon L | 160. | 420. | Peetre and Smith, 1974 |
Normal alkane RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | Apieson M | 160. | 420. | Ellren, Peetre, et al., 1974 | Chromosorb G AW DMCS (80-100 mesh) |
Normal alkane RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | Squalane | 419. | Szekely, Nefedov, et al., 1967 | Nitrogen, 5. K/min; Column length: 50. m; Column diameter: 0.25 mm; Tstart: 60. C; Tend: 250. C |
References
Go To: Top, Phase change data, Gas phase ion energetics 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]
Sommer, Goldberg, et al., 1946
Sommer, L.H.; Goldberg, G.M.; Derfman, E.; Whitmore, F.C.,
Organisilicaon Compounds V. β-Elimination Involving Silicon,
J. Am. Chem. Soc., 1946, 68, 1083. [all data]
McGlashan and McKinnon, 1977
McGlashan, M.L.; McKinnon, I.R.,
The vapor pressure, orthobaric volumes, and critical constants of tetramethylsilane,
J. Chem. Thermodyn., 1977, 9, 1205-12. [all data]
Voronkov, Baryshok, et al., 1988
Voronkov, M.G.; Baryshok, V.P.; Klyuchnikov, V.A.; Danilova, T.F.; Pepekin, V.I.; Korchagina, A.N.; Khudobin, Yu.I.,
Thermochemistry of organosilicon compounds,
Journal of Organometallic Chemistry, 1988, 345, 1-2, 27-38, https://doi.org/10.1016/0022-328X(88)80231-6
. [all data]
Aston, Kennedy, et al., 1941
Aston, J.G.; Kennedy, R.M.; Messerly, G.H.,
The heat capacity and entropy, heats of fusion and vaporization and the vapor pressure of silicon tetramethyl,
J. Am. Chem. Soc., 1941, 63, 2343-2348. [all data]
Bergmann and Haskelberg, 1941
Bergmann, F.; Haskelberg, L.,
Synthesis of Lipophilic Chemotherapeuticals. V. N 4 -Acyl-sulfanilamides 1a,
J. Am. Chem. Soc., 1941, 63, 8, 2243-2245, https://doi.org/10.1021/ja01853a062
. [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
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Harada, Atake, et al., 1977
Harada, M.; Atake, T.; Chihara, H.,
Thermodynamic properties of polymorphic phases of tetramethylsilane,
J. Chem. Thermodynam., 1977, 9, 523-534. [all data]
Shinoda, Enokida, et al., 1973
Shinoda, T.; Enokida, H.; Maeda, Y.; Tomita, H.; Mashiko, Y.,
Heat capacity of tetramethylsilane in the range from 2 to 26 K and premelting range,
Bull. Chem. Soc. Japan, 1973, 46, 48-52. [all data]
Murphy and Beauchamp, 1977
Murphy, M.K.; Beauchamp, J.L.,
Photoionization mass spectrometry of the fluoromethylsilanes (CH3)n F4-nSi (n = 1-4),
J. Am. Chem. Soc., 1977, 99, 2085. [all data]
Potzinger, Ritter, et al., 1975
Potzinger, P.; Ritter, A.; Krause, J.,
Massenspektrometrische Bestimmung von Bindungsenergien in siliciumorganischen Verbindungen,
Z. Naturforsch. A:, 1975, 30, 347. [all data]
MacLean and Sacher, 1974
MacLean, D.I.; Sacher, R.E.,
A study of some spectroscopic properties of Group IVA acetylides,
J. Organomet. Chem., 1974, 74, 197. [all data]
Jonas, Schweitzer, et al., 1973
Jonas, A.E.; Schweitzer, G.K.; Grimm, F.A.; Carlson, T.A.,
The photoelectron spectra of the tetrafluoro and tetramethyl compounds of the group IV elements,
J. Electron Spectrosc. Relat. Phenom., 1973, 1, 29. [all data]
Evans, Green, et al., 1972
Evans, S.; Green, J.C.; Joachim, P.J.; Orchard, A.F.; Turner, D.W.; Maier, J.P.,
Electronic structures of the Group IVB tetramethyls by helium-(I) photoelectron spectroscopy,
J. Chem. Soc. Faraday Trans. 2, 1972, 68, 905. [all data]
Lappert, Pedley, et al., 1971
Lappert, M.F.; Pedley, J.B.; Simpson, J.; Spalding, T.R.,
Bonding studies of compounds of boron and the Group IV elements. VI. Mass spectrometric studies on compounds Me4M and Me3M-M'Me3 (M and M'=C, Si, Ge, Sn, and Pb): thermochemical data,
J. Organomet. Chem., 1971, 29, 195. [all data]
Potzinger and Lampe, 1970
Potzinger, P.; Lampe, F.W.,
Thermochemistry of simple alkylsilanes,
J. Phys. Chem., 1970, 74, 719. [all data]
Distefano, 1970
Distefano, G.,
Photoionization study of tetramethylsilicon,
Inorg. Chem., 1970, 9, 1919. [all data]
Lappert, Simpson, et al., 1969
Lappert, M.F.; Simpson, J.; Spalding, T.R.,
Bonding studies of compounds of the group IV elements: ionisation potentials of the Me3M radicals,
J.Organometal. Chem., 1969, 17, PI. [all data]
Band, Davidson, et al., 1968
Band, S.J.; Davidson, I.M.T.; Lambert, C.A.,
Bond dissociation energies: electron impact studies on some trimethylsilyl compounds,
J. Chem. Soc. A, 1968, 2068. [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]
Khvostenko, Zykov, et al., 1981
Khvostenko, V.I.; Zykov, B.G.; Yuriev, V.P.; Mironov, V.F.; Kovel'zon, G.I.; Panasenko, A.A.; Sheludyakov, V.D.; Gailyunas, I.A.,
Study of d(π)-p(π) interaction in vinyl- and alkylsilicon-containing compounds by photoelectron spectroscopy,
J. Organomet. Chem., 1981, 218, 155. [all data]
Roberge, Sandorfy, et al., 1978
Roberge, R.; Sandorfy, C.; Matthews, J.I.; Strausz, O.P.,
The far ultraviolet HeI photoelectron spectra of alkyl and fluorine substituted silane derivatives,
J. Chem. Phys., 1978, 69, 5105. [all data]
Starzewski, Richter, et al., 1976
Starzewski, K.-H.A.O.; Richter, W.; Schmidbaur, H.,
Photoelektronenspektren und Struktur von Arsenyliden. P versus As: Ein Beitrag zur Problematik der ylidischen Bindung,
Chem. Ber., 1976, 109, 473. [all data]
deRidder and Dijkstra, 1967
deRidder, J.J.; Dijkstra, G.,
Mass spectra of the tetramethyl and tetraethyl compounds of carbon, silicon, germanium, tin and lead,
Rec. Trav. Chim., 1967, 86, 737. [all data]
Hobrock and Kiser, 1961
Hobrock, B.G.; Kiser, R.W.,
Electron impact spectroscopy of tetramethylsilicon, -tin and -lead,
J. Phys. Chem., 1961, 65, 2186. [all data]
Szepes and Baer, 1984
Szepes, L.; Baer, T.,
Dissociation dynamics of energy selected hexamethyldisilane ions and the heats of formation of (CH3)3Si+ and (CH3)3Si,
J. Am. Chem. Soc., 1984, 106, 273. [all data]
Szepes and Baer, 1984, 2
Szepes, L.; Baer, T.,
(CH3)3SiX tipusu vegyuletek vizsgalata fotoelectron-fotoion koincidenciaval,I. Meghatarozott belso energiaju hexametil-diszilan-ionok disszociaciojanak dinamikaja,
Magy. Kem. Foly., 1984, 90, 104. [all data]
Band, Davidson, et al., Commun. 1967
Band, S.J.; Davidson, I.M.T.; Lambert, C.A.; Stephenson, I.L.,
Bond dissociation energies and heats of formation of trimethylsilyl compounds,
Chem., Commun. 1967, 723. [all data]
Connor, Finney, et al., 1966
Connor, J.A.; Finney, G.; Leigh, G.J.; Haszeldine, R.N.; Robinson, P.J.; Sedgwick, R.D.; Simmons, R.F.,
Bond dissociation energies in organosilicon compounds,
Chem. Commun., 1966, 178. [all data]
Hess, Lampe, et al., 1964
Hess, G.G.; Lampe, F.W.; Sommer, L.H.,
Bond dissociation energies and ion energetics in organosilicon compounds by electron impact,
J. Am. Chem. Soc., 1964, 86, 3174. [all data]
Damrauer, Kass, et al., 1988
Damrauer, R.; Kass, S.R.; DePuy, C.H.,
Gas-Phase Acidities of Methylsilanes: C-H versus Si-H,
Organomet., 1988, 7, 3, 637, https://doi.org/10.1021/om00093a011
. [all data]
Wetzel and Brauman, 1988
Wetzel, D.M.; Brauman, J.I.,
Quantitative Measure of alpha-Silyl Carbanion Stabilization. The Electron Affinity of (Trimethylsilyl)methyl Radical,
J. Am. Chem. Soc., 1988, 110, 25, 8333, https://doi.org/10.1021/ja00233a008
. [all data]
DePuy and Damrauer, 1984
DePuy, C.H.; Damrauer, R.,
Reactions of organosilane anionic species with nitrous oxide,
Organometallics, 1984, 3, 362. [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,
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. [all data]
Riedo, Fritz, et al., 1976
Riedo, F.; Fritz, D.; Tarján, G.; Kováts, E.Sz.,
A tailor-made C87 hydrocarbon as a possible non-polar standard stationary phase for gas chromatography,
J. Chromatogr., 1976, 126, 63-83, https://doi.org/10.1016/S0021-9673(01)84063-2
. [all data]
Peetre and Smith, 1974
Peetre, I.-B.; Smith, B.E.F.,
Gas chromatographic investigation of organometallic compounds and their carbon analogues. IV. determination, calculation and correlation of Kováts retention indices for tetraalkylsilanes,
J. Chromatogr., 1974, 90, 1, 41-55, https://doi.org/10.1016/S0021-9673(01)94772-7
. [all data]
Ellren, Peetre, et al., 1974
Ellren, O.; Peetre, I.B.; Smith, B.E.F.,
Gas chromatographic investigation of organometallic compounds and their carbon analogues. V. Use of refractive index in conjunction with Kovats retention index for the identification of organosilicon compounds,
J. Chromatogr., 1974, 93, 2, 383-392, https://doi.org/10.1016/S0021-9673(01)85402-9
. [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, Phase change data, Gas phase ion energetics data, Gas Chromatography, References
- Symbols used in this document:
AE Appearance energy IE (evaluated) Recommended ionization energy Pc Critical pressure Tboil Boiling point Tc Critical temperature Ttriple Triple point temperature Vc Critical volume ΔHtrs Enthalpy of phase transition ΔStrs Entropy of phase transition ΔfusH Enthalpy of fusion ΔrG° Free energy of reaction at standard conditions ΔrH° Enthalpy of reaction at standard conditions ΔvapH Enthalpy of vaporization ΔvapH° Enthalpy of vaporization at standard conditions ΔvapS Entropy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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