Magnesium, bis(η5-2,4-cyclopentadien-1-yl)-

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Gas 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.

Data compiled by: José A. Martinho Simões

Quantity Value Units Method Reference Comment
Δfgas32.9 ± 1.1kcal/molReviewMartinho SimõesSelected data
Δfgas34.70 ± 0.79kcal/molReviewMartinho Simões 

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.

Data compiled by: José A. Martinho Simões

Quantity Value Units Method Reference Comment
Δfsolid16.6 ± 1.0kcal/molReviewMartinho SimõesSelected data
Δfsolid18. ± 0.7kcal/molCC-SBChipperfield, Sneyd, et al., 1979Value corrected based on a set of ancillary data by J.A. Martinho Simões; The enthalpy of combustion is not reported in Chipperfield, Sneyd, et al., 1979

Phase change 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 as indicated in comments:
AC - William E. Acree, Jr., James S. Chickos
MS - José A. Martinho Simões

Quantity Value Units Method Reference Comment
Δsub16.3 ± 0.31kcal/molN/APilcher and Skinner, 1983See also Hull, Reid, et al., 1967 and Turnbull, 1967.; AC
Δsub16.3 ± 0.31kcal/molRSCHull, Reid, et al., 1967, 2MS

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: José A. Martinho Simões

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

21,3-Cyclopentadiene (l) + magnesium (cr) = Magnesium, bis(η(5)-2,4-cyclopentadien-1-yl)- (cr) + Hydrogen (g)

By formula: 2C5H6 (l) + Mg (cr) = C10H10Mg (cr) + H2 (g)

Quantity Value Units Method Reference Comment
Δr-34.06 ± 0.69kcal/molRSCHull, Reid, et al., 1967, 2Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970.

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: Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

IE (eV) Method Reference Comment
8.0 ± 0.1EIBegun and Compton, 1973 
8.11PEEvans, Green, et al., 1972Vertical value

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C5H5Mg+11.0 ± 0.2?EIBegun and Compton, 1973 
Mg+13.9 ± 0.5?EIBegun and Compton, 1973 

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin Chemical Concepts
NIST MS number 150468

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UV/Visible spectrum

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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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Additional Data

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Source Ford, 1971
Owner INEP CP RAS, NIST OSRD
Collection (C) 2007 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS
Source reference RAS UV No. 15844
Instrument Cary 14

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, Notes

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

Martinho Simões
Martinho Simões, J.A., Private communication (see http://webbook.nist.gov/chemistry/om/). [all data]

Chipperfield, Sneyd, et al., 1979
Chipperfield, J.R.; Sneyd, J.C.R.; Webster, D.E., J. Organometal. Chem., 1979, 178, 177. [all data]

Pilcher and Skinner, 1983
Pilcher, G.; Skinner, H.A., Thermochemistry of organometallic compounds, 1983, 43-90, https://doi.org/10.1002/9780470771686.ch2 . [all data]

Hull, Reid, et al., 1967
Hull, H.S.; Reid, Allen Forrest; Turnbull, Alan G., Heat of formation and bond energy of bis(cyclopentadienyl)magnesium, Inorg. Chem., 1967, 6, 4, 805-807, https://doi.org/10.1021/ic50050a032 . [all data]

Turnbull, 1967
Turnbull, AG, Thermochemistry of biscyclopentsdienyl metal compounds, Aust. J. Chem., 1967, 20, 12, 2757-621, https://doi.org/10.1071/CH9672757 . [all data]

Hull, Reid, et al., 1967, 2
Hull, H.S.; Reid, A.F.; Turnbull, A.G., Inorg. Chem., 1967, 6, 805. [all data]

Pedley and Rylance, 1977
Pedley, J.B.; Rylance, J., Computer Analysed Thermochemical Data: Organic and Organometallic Compounds, University of Sussex, Brigton, 1977. [all data]

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

Begun and Compton, 1973
Begun, G.M.; Compton, R.N., Electron impact ionization studies of ferrocene, cobaltocene, nickelocene, and magnesocene, J. Chem. Phys., 1973, 58, 2271. [all data]

Evans, Green, et al., 1972
Evans, S.; Green, M.L.H.; Jewitt, B.; Orchard, A.F.; Pygall, C.F., Electronic structure of metal complexes containing π-cyclopentadienyl and related ligands, J. Chem. Soc. Faraday Trans. 2, 1972, 68, 1847. [all data]

Ford, 1971
Ford, W.T., J. Organometallic Chem., 1971, 32, 27. [all data]


Notes

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