(CH3)2Si

Formula: C₂H₆Si
Molecular weight: 58.1545
IUPAC Standard InChI: InChI=1S/C2H6Si/c1-3-2/h1-2H3
IUPAC Standard InChIKey: JZZIHCLFHIXETF-UHFFFAOYSA-N
CAS Registry Number: 6376-86-9
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.
Permanent link for this species. Use this link for bookmarking this species for future reference.
Information on this page:
Data at other public NIST sites:
- Gas Phase Kinetics Database
Options:
- Switch to SI units

Reaction thermochemistry data

Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References, Notes

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

C₂H₅Si^- + = (CH3)2Si

By formula: C₂H₅Si^- + H⁺ = C₂H₆Si

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	380.7 ± 5.1	kcal/mol	G+TS	Damrauer, DePuy, et al., 1986	gas phase; May have rearranged to 2-sila-allyl anion: G3MP2B3 calculations indicate an acidity of 361 kcal/mol
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	374.0 ± 5.0	kcal/mol	IMRB	Damrauer, DePuy, et al., 1986	gas phase; May have rearranged to 2-sila-allyl anion: G3MP2B3 calculations indicate an acidity of 361 kcal/mol

Gas phase ion energetics data

Go To: Top, Reaction thermochemistry data, Vibrational and/or electronic energy levels, References, Notes

Data compiled by: John E. Bartmess

View reactions leading to C₂H₆Si⁺ (ion structure unspecified)

De-protonation reactions

C₂H₅Si^- + = (CH3)2Si

By formula: C₂H₅Si^- + H⁺ = C₂H₆Si

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	380.7 ± 5.1	kcal/mol	G+TS	Damrauer, DePuy, et al., 1986	gas phase; May have rearranged to 2-sila-allyl anion: G3MP2B3 calculations indicate an acidity of 361 kcal/mol
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	374.0 ± 5.0	kcal/mol	IMRB	Damrauer, DePuy, et al., 1986	gas phase; May have rearranged to 2-sila-allyl anion: G3MP2B3 calculations indicate an acidity of 361 kcal/mol

Vibrational and/or electronic energy levels

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References, Notes

Data compiled by: Marilyn E. Jacox

State: ?

Energy (cm^-1)	Med.	References


T_x_d = 22200	Ar	Drahnak, Michl, et al., 1979
		Drahnak, Michl, et al., 1981
		Arrington, Klingensmith, et al., 1984
		Maier, Mihm, et al., 1984

State: ?

Energy (cm^-1)	Med.	References


T_x_d = 22200	N₂	Drahnak, Michl, et al., 1979
		Drahnak, Michl, et al., 1981
		Arrington, Klingensmith, et al., 1984
		Maier, Mihm, et al., 1984

State: X

Vib. sym.	No.	Approximate type of mode	cm^-1		Med.	Method	References


a₁	4	CH₃ s-deform.	1222	s	Ar	IR	Drahnak, Michl, et al., 1979 Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
	5	CH₃ plan. rock	844	vs	Ar	IR	Reisenauer, Mihm, et al., 1982 Arrington, Klingensmith, et al., 1984 Maier, Mihm, et al., 1984 Raabe, Vancik, et al., 1986
	5	CH₃ plan. rock	844	vs	N₂	IR	Reisenauer, Mihm, et al., 1982 Arrington, Klingensmith, et al., 1984 Maier, Mihm, et al., 1984 Raabe, Vancik, et al., 1986
	6	Si-C stretch	690	w	Ar	IR	Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
	6	Si-C stretch	690	w	N₂	IR	Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
b₁	12	CH₃ stretch	2942	m	Ar	IR	Raabe, Vancik, et al., 1986
	13	CH₃ a-deform.	1435	m	Ar	IR	Drahnak, Michl, et al., 1981 Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
b₂	17	CH₃ stretch	2977	s	Ar	IR	Raabe, Vancik, et al., 1986
	19	CH₃ s-deform.	1212	s	Ar	IR	Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
	20	CH₃ plan. rock	803	vs	Ar	IR	Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
	20	CH₃ plan. rock	803	vs	N₂	IR	Arrington, Klingensmith, et al., 1984 Raabe, Vancik, et al., 1986
	21	Si-C stretch	735	m T	Ar	IR	Arrington, Klingensmith, et al., 1984
	21	Si-C stretch	735	m T	N₂	IR	Arrington, Klingensmith, et al., 1984

Additional references: Jacox, 1994, page 399

Notes

Weak

Medium

Strong

Very strong

Tentative assignment or approximate value

Energy separation between the band maximum of the excited electronic state and the v = 0 level of the ground state.

Photodissociation threshold

References

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, Notes

Damrauer, DePuy, et al., 1986
Damrauer, R.; DePuy, C.H.; Davidson, I.M.T.; Hughes, K.J., Gas phase ion chemistry of dimethylsilylene, Organometallics, 1986, 5, 2054. [all data]

Drahnak, Michl, et al., 1979
Drahnak, T.J.; Michl, J.; West, R., Dimethylsilylene, (CH3)2Si, J. Am. Chem. Soc., 1979, 101, 18, 5427, https://doi.org/10.1021/ja00512a059 . [all data]

Drahnak, Michl, et al., 1981
Drahnak, T.J.; Michl, J.; West, R., Photoisomerization of dimethylsilylene to 2-silapropene and thermal reversion to dimethylsilylene, J. Am. Chem. Soc., 1981, 103, 7, 1845, https://doi.org/10.1021/ja00397a047 . [all data]

Arrington, Klingensmith, et al., 1984
Arrington, C.A.; Klingensmith, K.A.; West, R.; Michl, J., Polarized infrared spectroscopy of matrix-isolated dimethylsilylene and 1-methylsilene, J. Am. Chem. Soc., 1984, 106, 3, 525, https://doi.org/10.1021/ja00315a010 . [all data]

Maier, Mihm, et al., 1984
Maier, G.; Mihm, G.; Reisenauer, H.P.; Littmann, D., Hetero-π-Systeme, 9. Über die Beziehungen zwischen Silaethenen und Methylsilylenen, Chem. Ber., 1984, 117, 7, 2369, https://doi.org/10.1002/cber.19841170709 . [all data]

Raabe, Vancik, et al., 1986
Raabe, G.; Vancik, H.; West, R.; Michl, J., IR transition moment directions in matrix-isolated dimethylsilylene and 1-methylsilene, J. Am. Chem. Soc., 1986, 108, 4, 671, https://doi.org/10.1021/ja00264a017 . [all data]

Reisenauer, Mihm, et al., 1982
Reisenauer, H.P.; Mihm, G.; Maier, G., Reversible Photoisomerisierung zwischen Silaethenen und Methylsilylenen (Methylsilandiylen), Angew. Chem., 1982, 94, 11, 864, https://doi.org/10.1002/ange.19820941110 . [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Notes

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Vibrational and/or electronic energy levels, References

Symbols used in this document:

Δ_rG° Free energy of reaction at standard conditions

Δ_rH° Enthalpy of reaction at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
Customer support for NIST Standard Reference Data products.

Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions