magnesium dihydride

• Formula: H₂Mg
• Molecular weight: 26.3209
• IUPAC Standard InChI: InChI=1S/Mg.2H Copy

  
• IUPAC Standard InChIKey: RSHAOIXHUHAZPM-UHFFFAOYSA-N Copy
• CAS Registry Number: 7693-27-8
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Other names: Magnesium hydride
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• Information on this page:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Data at other public NIST sites:
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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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.

Solid Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
    C_p = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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Reaction 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: John E. Bartmess

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

HMg^- +  =

By formula: HMg^- + H⁺ = H₂Mg

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 compiled by: John E. Bartmess

De-protonation reactions

HMg^- +  =

By formula: HMg^- + H⁺ = H₂Mg

Vibrational and/or electronic energy levels

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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: Marilyn E. Jacox

State:   X

Additional references: Jacox, 1994, page 14; Jacox, 1998, page 125; Shayesteh, Appadoo, et al., 2004; Shayesteh and Bernath, 2006

Notes

References

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

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Rackwitz, Feldman, et al., 1977
Rackwitz, R.; Feldman, D.; Kaiser, H.J.; Heincke, E., Photodetachment bei einigen zweiatomigen negativen hydridionen: BeH-, MgH-, CaH-, ZnH-, PH-, AsH-, Z. Naturforsch. A:, 1977, 32, 594. [all data]

Hinde, 2000
Hinde, R.J., Ab initio gas-phase acidities of NaH, MgH2, and AlH3, J. Phys. Chem. A, 2000, 104, 32, 7580-7585, https://doi.org/10.1021/jp994138j . [all data]

Shayesteh, Appadoo, et al., 2003
Shayesteh, A.; Appadoo, D.R.T.; Gordon, I.; Bernath, P.F., The vibration--rotation emission spectrum of MgH[sub 2], J. Chem. Phys., 2003, 119, 15, 7785, https://doi.org/10.1063/1.1609973 . [all data]

Wang and Andrews, 2004
Wang, X.; Andrews, L., Infrared Spectra of Magnesium Hydride Molecules, Complexes, and Solid Magnesium Dihydride, J. Phys. Chem. A, 2004, 108, 52, 11511, https://doi.org/10.1021/jp046410h . [all data]

Tague and Andrews, 1994
Tague, T.J., Jr.; Andrews, L., Pulsed Laser Evaporated Magnesium Atom Reactions with Hydrogen: Infrared Spectra of Five Magnesium Hydride Molecules, J. Phys. Chem., 1994, 98, 35, 8611, https://doi.org/10.1021/j100086a004 . [all data]

McCaffrey, Parnis, et al., 1985
McCaffrey, J.G.; Parnis, J.M.; Ozin, G.A.; Breckenridge, W.H., Photochemical synthesis of magnesium dihydride and methyl magnesium hydride in cryogenic matrixes, J. Phys. Chem., 1985, 89, 23, 4945, https://doi.org/10.1021/j100269a012 . [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]

Jacox, 1998
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules: supplement A, J. Phys. Chem. Ref. Data, 1998, 27, 2, 115-393, https://doi.org/10.1063/1.556017 . [all data]

Shayesteh, Appadoo, et al., 2004
Shayesteh, A.; Appadoo, D.R.T.; Gordon, I.; Bernath, P.F., The antisymmetric stretching fundamental band of free MgD, Can. J. Chem., 2004, 82, 6, 947, https://doi.org/10.1139/v04-043 . [all data]

Shayesteh and Bernath, 2006
Shayesteh, A.; Bernath, P.F., Rotational [script-l]-type resonance in BeH[sub 2], BeD[sub 2], and MgH[sub 2], J. Chem. Phys., 2006, 124, 15, 156101, https://doi.org/10.1063/1.2189859 . [all data]

Notes

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• Symbols used in this document:
  

  S°solid	Entropy of solid at standard conditions
  ΔfH°solid	Enthalpy of formation of solid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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