Urea, N,N'-dimethyl-

• Formula: C₃H₈N₂O
• Molecular weight: 88.1084
• IUPAC Standard InChI: InChI=1S/C3H8N2O/c1-4-3(6)5-2/h1-2H3,(H2,4,5,6) Copy

  
• IUPAC Standard InChIKey: MGJKQDOBUOMPEZ-UHFFFAOYSA-N Copy
• CAS Registry Number: 96-31-1
• 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:
  • dimethylurea
• Other names: Urea, 1,3-dimethyl-; sym-Dimethylurea; N,N'-Dimethylurea; Symmetric dimethylurea; 1,3-Dimethylurea; (CH3NH)2CO; 1,1'-Dimethylurea; DMU; N,N'-Dimethylharnstoff; NSC 14910
• Information on this page:
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Mass spectrum (electron ionization)
• Options:
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Phase change data

Go To: Top, 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 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
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of sublimation

Enthalpy of fusion

Entropy of fusion

Gas phase ion energetics data

Go To: Top, Phase change data, 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

Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

Appearance energy determinations

References

Go To: Top, Phase change data, Gas phase ion energetics data, Notes

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

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]

Davies, Finch, et al., 1991
Davies, R.H.; Finch, A.; Hill, J.O., The thermochemistry of 1,3-dimethylurea and 1,3-dimethylurea nitrate, Thermochim. Acta, 1991, 184, 243-50. [all data]

DellaGatta and Ferro, 1987
DellaGatta, G.; Ferro, D., Enthalpies of fusion and solid-to-solid transition, entropies of fusion for urea and twelve alkylurea, Thermochim. Acta, 1987, 122, 143-52. [all data]

Zordan, Hurkot, et al., 1972
Zordan, T.A.; Hurkot, D.G.; Peterson, M.; Hepler, L.G., Enthalpies and entropies of melting from differential scanning calorimetry and freezing point depressions: urea, methylurea, 1, 1-dimethylurea, 1, 3- dimethylurea, tetramethylurea, and thiourea, Thermochim. Acta, 1972, 5, 21. [all data]

Kabo, Miroshnichenko, et al., 1990
Kabo, G.Ya.; Miroshnichenko, E.A.; Frenkel, M.L.; Kozyro, A.A.; Simirsky, V.V.; Krasulin, A.P.; Vorob'eva, V.P.; Lebedev, Yu.A., Thermochemistry of Alkyl Derivatives of Urea, Izv. Akad. Nauk SSSR, Ser. Khim., 1990, No. 4, 750-5. [all data]

Emel'yanenko, Kabo, et al., 2006
Emel'yanenko, Vladimir N.; Kabo, Gennady J.; Verevkin, Sergey P., Measurement and Prediction of Thermochemical Properties: Improved Increments for the Estimation of Enthalpies of Sublimation and Standard Enthalpies of Formation of Alkyl Derivatives of Urea, J. Chem. Eng. Data, 2006, 51, 1, 79-87, https://doi.org/10.1021/je050230z . [all data]

Zaitsau, Kabo, et al., 2003
Zaitsau, Dz; Kabo, G.J.; Kozyro, A.A.; Sevruk, V.M., The effect of the failure of isotropy of a gas in an effusion cell on the vapor pressure and enthalpy of sublimation for alkyl derivatives of carbamide, Thermochimica Acta, 2003, 406, 1-2, 17-28, https://doi.org/10.1016/S0040-6031(03)00231-4 . [all data]

Kabo, Miroshnichenko, et al., 1990, 2
Kabo, G.Ya.; Miroshnichenko, E.A.; Frenkel, M.L.; Kozyro, A.A.; Simirskii, V.V.; Krasulin, A.P.; Vorob'eva, V.P.; Lebedev, Yu.A., Thermochemistry of urea alkyl derivatives, Bull. Acad. Sci. USSR, Div. Chem. Sci., 1990, 662-667. [all data]

Piacente, Ferro, et al., 1990
Piacente, V.; Ferro, D.; Gatta, G. Della, Sublimation enthalpy of eleven alkyl derivatives of urea, Thermochimica Acta, 1990, 158, 1, 79-85, https://doi.org/10.1016/0040-6031(90)80054-3 . [all data]

Ferro, Barone, et al., 1987
Ferro, D.; Barone, G.; Della Gatta, G.; Piacente, V., Vapour pressures and sublimation enthalpies of urea and some of its derivatives, The Journal of Chemical Thermodynamics, 1987, 19, 9, 915-923, https://doi.org/10.1016/0021-9614(87)90038-3 . [all data]

Della Gatta and Ferro, 1987
Della Gatta, G.; Ferro, D., Enthalpies of fusion and solid-to-solid transition, entropies of fusion for urea and twelve alkylureas, Thermochim. Acta, 1987, 122, 143-152. [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]

Baldwin, Kirkien-Konasiewicz, et al., 1966
Baldwin, M.; Kirkien-Konasiewicz, A.; Loudon, A.G.; Maccoll, A.; Smith, D., Localised or delocalised charges in molecule-ions?, Chem. Commun., 1966, 574. [all data]

Dougherty, Wittel, et al., 1976
Dougherty, D.; Wittel, K.; Meeks, J.; McGlynn, S.P., Photoelectron spectroscopy of carbonyls. Ureas, uracils, and thymine, J. Am. Chem. Soc., 1976, 98, 3815. [all data]

Loudon and Webb, 1977
Loudon, A.G.; Webb, K.S., The nature of the [C₂H₆N]⁺ and [CH₄N]⁺ ions formed by electron impact on methylated formamides, acetamides, ureas, thioureas and hexamethylphosphoramide, Org. Mass Spectrom., 1977, 12, 283. [all data]

Notes

Go To: Top, Phase change data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  Ttriple	Triple point temperature
  ΔfusH	Enthalpy of fusion
  ΔfusS	Entropy of fusion
  ΔsubH	Enthalpy of sublimation
  ΔsubH°	Enthalpy of sublimation at standard conditions

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