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magnesium dihydride


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.

Quantity Value Units Method Reference Comment
Deltafsolid-18.20kcal/molReviewChase, 1998Data last reviewed in September, 1963
Quantity Value Units Method Reference Comment
solid7.416cal/mol*KReviewChase, 1998Data last reviewed in September, 1963

Solid Phase Heat Capacity (Shomate Equation)

Cp° = 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
    Cp = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. - 2000.
A 3.180321
B 24.65600
C -14.42830
D 2.911011
E -0.079568
F -20.39400
G 4.082300
H -18.20010
ReferenceChase, 1998
Comment Data last reviewed in September, 1963

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

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Individual Reactions

HMg- + Hydrogen cation = magnesium dihydride

By formula: HMg- + H+ = H2Mg

Quantity Value Units Method Reference Comment
Deltar359.3 ± 2.4kcal/molD-EARackwitz, Feldman, et al., 1977gas phase; Caln: «DELTA»Hacid=363.8 Hinde, 2000

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- + Hydrogen cation = magnesium dihydride

By formula: HMg- + H+ = H2Mg

Quantity Value Units Method Reference Comment
Deltar359.3 ± 2.4kcal/molD-EARackwitz, Feldman, et al., 1977gas phase; Caln: «DELTA»Hacid=363.8 Hinde, 2000

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


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

Piu 2 Bend 437 T gas IR Shayesteh, Appadoo, et al., 2003
2 Bend 450.4 Ne IR Wang and Andrews, 2004
2 Bend 439.8 Ar IR Tague and Andrews, 1994
2 Bend 430 Kr IR McCaffrey, Parnis, et al., 1985
2 Bend 417 Xe IR McCaffrey, Parnis, et al., 1985
2 Bend 450.4 p-H2 IR Wang and Andrews, 2004
2 Bend 450.1 H2 IR Wang and Andrews, 2004
b2 3 Asym. stretch 1588.67 gas IR Shayesteh, Appadoo, et al., 2003
3 Asym. stretch 1576.8 Ne IR Wang and Andrews, 2004
3 Asym. stretch 1574.0 Ne IR Wang and Andrews, 2004
Sigmau+ 3 Asym. stretch 1571.9 Ar IR Tague and Andrews, 1994
3 Asym. stretch 1558 Kr IR McCaffrey, Parnis, et al., 1985
3 Asym. stretch 1569 Xe IR McCaffrey, Parnis, et al., 1985
3 Asym. stretch 1544 Xe IR McCaffrey, Parnis, et al., 1985
3 Asym. stretch 1577.4 p-H2 IR Wang and Andrews, 2004
3 Asym. stretch 1569.5 H2 IR Wang and Andrews, 2004

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

Notes

TTentative assignment or approximate value

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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