Hydrazine, 1,1-dimethyl-

• Formula: C₂H₈N₂
• Molecular weight: 60.0983
• IUPAC Standard InChI: InChI=1S/C2H8N2/c1-4(2)3/h3H2,1-2H3 Copy

  
• IUPAC Standard InChIKey: RHUYHJGZWVXEHW-UHFFFAOYSA-N Copy
• CAS Registry Number: 57-14-7
• 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.
• Species with the same structure:
  • dimethylhydrazine
• Other names: as-Dimethylhydrazine; Dimazin; Dimazine; Hydrazine, N,N-dimethyl-; N,N-Dimethylhydrazine; UDMH; 1,1-Dimethylhydrazine; (CH3)2NNH2; Unsym-dimethylhydrazine; Dimethylhydrazine, unsymmetrical; Dimethylhydrazine, unsym.; 1,1-Dimethylhydrazin; asymmetric Dimethylhydrazine; uns-Dimethylhydrazine; Niesymetryczna dwu metylohydrazyna; Rcra waste number U098; UN 1163; Unsymmetrical dimethylhydrazine; u-Dimethylhydrazine; gem-Dimethylhydrazine; NSC 60517
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Gas Chromatography
  • References
  • Notes
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

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, Notes

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

Data compiled by: Donald R. Burgess, Jr.

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, NIST Free Links, 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
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, NIST Free Links, 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing
AC - William E. Acree, Jr., James S. Chickos

Reduced pressure boiling point

Enthalpy of vaporization

Entropy of vaporization

Antoine Equation Parameters

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, NIST Free Links, 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:
HL - Edward P. Hunter and Sharon G. Lias
L - 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
LL - Sharon G. Lias and Joel F. Liebman

Ionization energy determinations

Appearance energy determinations

IR Spectrum

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

Gas Phase Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, IR Spectrum, Gas Chromatography, NIST Free Links, 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

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

Additional Data

Gas Chromatography

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

Normal alkane RI, non-polar column, temperature ramp

View large format table.

References

Go To: Top, Gas phase thermochemistry data, 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.

Donovan, Shomate, et al., 1960
Donovan, T.M.; Shomate, C.H.; McBride, W.R., The heat of combustion of tetramethyltetrazene and 1,1-dimethylhydrazine, J. Phys. Chem., 1960, 64, 281-282. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Aston, Rock, et al., 1952
Aston, J.G.; Rock, E.J.; Isserow, S., The heats of combustion of the methyl substituted hydrazines and some observations on the burning of volatile liquids, J. Am. Chem. Soc., 1952, 74, 2484-24. [all data]

Aston, Wood, et al., 1953
Aston, J.G.; Wood, J.L.; Zolki, T.P., The thermodynamic properties and configuration of unsymmetrical dimethylhydrazine, J. Am. Chem. Soc., 1953, 75, 6202-6204. [all data]

Weast and Grasselli, 1989
CRC Handbook of Data on Organic Compounds, 2nd Editon, Weast,R.C and Grasselli, J.G., ed(s)., CRC Press, Inc., Boca Raton, FL, 1989, 1. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

McMillan, 1967
McMillan, J.A., Hydrazine-1,1-Dimethylhydrazine Solid-Liquid Phase Diagram, J. Chem. Eng. Data, 1967, 12, 39. [all data]

Aston, Wood, et al., 1953, 2
Aston, J.G.; Wood, J.L.; Zolki, T.P., The Thermodynamic Properties and Configuration of Unsymmetrical Dimethylhydrazine, J. Am. Chem. Soc., 1953, 75, 6202. [all data]

Aston, Wood, et al., 1953, 3
Aston, J.G.; Wood, J.L.; Zolki, T.P., The thermodynamic properties and configuration of unsymmetrical dimethylhydrazine, J. Am. Chem. Soc., 1953, 75, 6202-62. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Bourret-Courchesne, Ye, et al., 2000
Bourret-Courchesne, E.; Ye, Q.; Peters, D.W.; Arnold, J.; Ahmed, M.; Irvine, S.J.C.; Kanjolia, R.; Smith, L.M.; Rushworth, S.A., Pyrolysis of dimethylhydrazine and its co-pyrolysis with triethylgallium, Journal of Crystal Growth, 2000, 217, 1-2, 47-54, https://doi.org/10.1016/S0022-0248(00)00398-5 . [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Boublik, Fried, et al., 1984
Boublik, T.; Fried, V.; Hala, E., The Vapour Pressures of Pure Substances: Selected Values of the Temperature Dependence of the Vapour Pressures of Some Pure Substances in the Normal and Low Pressure Region, 2nd ed., Elsevier, New York, 1984, 972. [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]

Mautner(Meot-Ner), Nelsen, et al., 1984
Mautner(Meot-Ner), M.; Nelsen, S.F.; Willi, M.R.; Frigo, T.B., Special effects of an unusually large neutral to radical cation geometry change. Adiabatic ionization energies and proton affinities of alkylhydrazines, J. Am. Chem. Soc., 1984, 106, 7384. [all data]

Vovna, Vilesov, et al., 1975
Vovna, V.I.; Vilesov, F.I.; Lopatin, S.N., Photoelectron spectra of hydrazine and some alkyl derivatives, Opt. Spectrosc., 1975, 38, 143. [all data]

Bodor, Dewar, et al., 1970
Bodor, N.; Dewar, M.J.S.; Jennings, W.B.; Worley, S.D., Photoelectron spectra of molecules-IV.Ionization potentials and heats of formation of some hydrazines and amines, Tetrahedron, 1970, 26, 4109. [all data]

Akopyan and Vilesov, 1963
Akopyan, M.E.; Vilesov, F.I., Decay of the molecular ions formed in photoionization of hydrazine and some of its alkyl derivatives, Kinetika i Kataliz, 1963, 4, 39, In original 32. [all data]

Akopyan, Vilesov, et al., 1963
Akopyan, M.E.; Vilesov, F.I.; Terenin, A.N., Mass spectrometric investigation of photoionization of molecules and dissociation of excited molecular ions, Izv. Akad. Nauk SSSR, Ser. Fiz., 1963, 27, 1083, In original 1054. [all data]

Dibeler, Franklin, et al., 1959
Dibeler, V.H.; Franklin, J.L.; Reese, R.M., Electron impact studies of hydrazine and the methyl-substituted hydrazines, J. Am. Chem. Soc., 1959, 81, 68. [all data]

Rademacher, 1975
Rademacher, P., Acyclische Hydrazine, Chem. Ber., 1975, 108, 1548. [all data]

Kimura, Katsumata, et al., 1975
Kimura, K.; Katsumata, S.; Osafune, K., Photoelectron spectroscopic study of skew compounds. Methylhydrazine and unsymmetrical dimethylhydrazine, Bull. Chem. Soc. Jpn., 1975, 48, 2736. [all data]

Nelsen and Buschek, 1974
Nelsen, S.F.; Buschek, J.M., Photoelectron spectra of hydrazines. IV. Empirical estimation of lone pair-lone pair dihedral angles and prediction of lone pair ionization potentials for some cyclic and bicyclic hydrazines, J. Am. Chem. Soc., 1974, 96, 6982. [all data]

Nelsen and Buschek, 1974, 2
Nelsen, S.F.; Buschek, J.M., Photoelectron spectra of hydrazines. III. Evidence for similar lone pair-lone pair dihedral angles for acyclic hydrazines, J. Am. Chem. Soc., 1974, 96, 2392. [all data]

Burgers, Drewello, et al., 1989
Burgers, P.C.; Drewello, T.; Schwarz, H.; Terlouw, J.K., CH₅N₂ hydrazyl radicals, cations and dication radicals studied by mass spectrometry. Is the N-protonated formaldehyde hydrazon cation ⁺CH₂-NH-NH₂ a bridged species?, Int. J. Mass Spectrom. Ion Processes, 1989, 95, 157. [all data]

Fisher and Henderson, 1967
Fisher, I.P.; Henderson, E., Mass spectrometry of free radicals, J. Chem. Soc. Faraday Trans., 1967, 63, 1342. [all data]

Gowenlock, Jones, et al., 1961
Gowenlock, B.G.; Jones, P.P.; Majer, J.R., Bond dissociation energies in some molecules containing alkyl substituted CH₃, NH₂, and OH, J. Chem. Soc. Faraday Trans., 1961, 57, 23. [all data]

Foner and Hudson, 1970
Foner, S.N.; Hudson, R.L., Mass spectrometric studies of atom-molecule reactions using high-intensity crossed molecular beams, J. Chem. Phys., 1970, 53, 4377. [all data]

Foner and Hudson, 1962
Foner, S.N.; Hudson, R.L., Mass spectrometry of inorganic free radicals, Advan. Chem. Ser., 1962, 36, 34. [all data]

Zenkevich, 2005
Zenkevich, I.G., Experimentally measured retention indices., 2005. [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  IE (evaluated)	Recommended ionization energy
  S°liquid	Entropy of liquid at standard conditions
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  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
• 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.