Dicobalt octacarbonyl

Formula: C₈Co₂O₈
Molecular weight: 341.9472
IUPAC Standard InChI: InChI=1S/8CO.2Co/c8*1-2;;
IUPAC Standard InChIKey: NFWSABSVGZVHCA-UHFFFAOYSA-N
CAS Registry Number: 10210-68-1
Chemical structure:
This structure is also available as a 2d Mol file
Other names: Cobalt, di-μ-carbonylhexacarbonyldi-, (Co-Co); Cobalt carbonyl (Co2(CO)8); Cobalt tetracarbonyl dimer; Di-μ-carbonylhexacarbonyldicobalt; Dicobalt carbonyl (Co2(CO)8); Octacarbonyldicobalt; Co2(CO)8; Cobalt carbonyl; Cobalt, di-μ-carbonylhexacarbonyldi-; Cobalt octacarbonyl
Permanent link for this species. Use this link for bookmarking this species for future reference.
Information on this page:
Other data available:
- Gas phase ion energetics data
- Mass spectrum (electron ionization)
Options:
- Switch to calorie-based units

Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References, Notes

Data compiled by: José A. Martinho Simões

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-1183.0 ± 9.1	kJ/mol	Review	Martinho Simões
Δ_fH°_gas	-1185.2 ± 9.4	kJ/mol	Review	Martinho Simões
Δ_fH°_gas	-1184.1 ± 6.9	kJ/mol	Review	Martinho Simões	Selected data. Average of the values from Connor, Skinner, et al., 1973 and Gardner, Cartner, et al., 1975.

Condensed phase thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, References, Notes

Data compiled by: José A. Martinho Simões

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_solid	-1248.2 ± 8.5	kJ/mol	Review	Martinho Simões
Δ_fH°_solid	-1250.4 ± 8.8	kJ/mol	Review	Martinho Simões
Δ_fH°_solid	-1249.3 ± 6.1	kJ/mol	Review	Martinho Simões	Selected data. Average of the values from Connor, Skinner, et al., 1973 and Gardner, Cartner, et al., 1975.

Phase change data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, References, Notes

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
Δ_subH°	65.2 ± 3.3	kJ/mol	N/A	Pilcher and Skinner, 1983	See also Cardner, Gartner, et al., 1975.; AC
Δ_subH°	65.2 ± 3.3	kJ/mol	TD-HFC	Gardner, Cartner, et al., 1975	Another value for the enthalpy of sublimation has been reported: 75.3±6.3 Cartner, Robinson, et al., 1973.; MS

Enthalpy of sublimation

Δ_subH (kJ/mol)	Temperature (K)	Method	Reference	Comment
84.3 ± 0.5	271.	TE	Garner, Chandra, et al., 1995	Based on data from 264. to 278. K.; AC
103.8	301.5	A	Stephenson and Malanowski, 1987	Based on data from 288. to 315. K. See also Baev, 1968.; AC
75.3 ± 6.3	207. to 287.	EM	Cartner, Robinson, et al., 1973, 2	AC

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, References, Notes

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

Dicobalt octacarbonyl (solution) + (solution) = 2 (solution)

By formula: C₈Co₂O₈ (solution) + H₂ (solution) = 2C₄HCoO₄ (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	19.7 ± 0.8	kJ/mol	EqS	Rathke, Klingler, et al., 1992	solvent: Supercritical carbon dioxide; Temperature range: 333-453 K. The results corrected for 1 atm pressure of H2 are 16.7 kJ/mol and -17.6 J/(mol K) Rathke, Klingler, et al., 1992
Δ_rH°	13.0 ± 0.9	kJ/mol	EqS	Bor, 1986	solvent: n-Hexane; Temperature range: ca. 300-420 K
Δ_rH°	26.4	kJ/mol	KinS	Alemdaroglu, Penninger, et al., 1976	solvent: n-Heptane; The reaction enthalpy relies on the experimental values for the forward and reverse activation enthalpies, 72.4 and 46.0 kJ/mol, respectively Alemdaroglu, Penninger, et al., 1976. A rather different value has, however, been reported for the activation enthalpy of the forward reaction, 104.6 kJ/mol Ungváry, 1972
Δ_rH°	27.6	kJ/mol	EqS	Alemdaroglu, Penninger, et al., 1976	solvent: n-Heptane; Temperature range: 353-428 K
Δ_rH°	13.4	kJ/mol	EqS	Ungváry, 1972	solvent: n-Heptane; Temperature range: 307-428 K. The results corrected for 1 atm pressure of H2 are 18.0 kJ/mol and -10.9 J/(mol K) Rathke, Klingler, et al., 1992

Dicobalt octacarbonyl (g) = 2 (g)

By formula: C₈Co₂O₈ (g) = 2C₄CoO₄ (g)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	64.	kJ/mol	EST	Connor, 1977	Please also see Pilcher and Skinner, 1982 and Martinho Simões and Beauchamp, 1990. The enthalpy of formation relies on -1184.1 ± 6.9 kJ/mol for the enthalpy of formation of Co2(CO)8(g).
Δ_rH°	60. ± 13.	kJ/mol	EG/EIMS	Bidinosti and McIntyre, 1970	The reaction enthalpy includes an estimated correction to 298 K. A value of 60.7 ± 8.4 kJ/mol was reported at an average temperature of 330 K Bidinosti and McIntyre, 1970.

Dicobalt octacarbonyl (solution) = C₇Co₂O₇ (solution) + (solution)

By formula: C₈Co₂O₈ (solution) = C₇Co₂O₇ (solution) + CO (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	92.7	kJ/mol	KinS	Ungváry and Markó, 1974	solvent: Heptane; Temperature range: 298-328 K
Δ_rH°	87.9	kJ/mol	KinS	Ungváry, 1972	solvent: Heptane; Temperature range: 307-337 K

0.5 Dicobalt octacarbonyl (solution) + (cr) = C₄CoNaO₄ (solution)

By formula: 0.5C₈Co₂O₈ (solution) + Na (cr) = C₄CoNaO₄ (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-318. ± 11.	kJ/mol	RSC	Kiss, Nolan, et al., 1994	solvent: Tetrahydrofuran; The reaction enthalpy was calculated from the enthalpies of the following reactions: 0.5Co2(CO)8(solution) + (Na)(Ph2CO)(solution) = (Na)[Co(CO)4](solution) + Ph2CO(solution), -157. ± 11. kJ/mol, and Ph2CO(solution) + Na(cr) = (Na)(Ph2CO)(solution), -161.1 ± 2.5 kJ/mol Kiss, Nolan, et al., 1994.

(solution) + Dicobalt octacarbonyl (solution) = 2C₉CoMnO₉ (solution)

By formula: C₁₀Mn₂O₁₀ (solution) + C₈Co₂O₈ (solution) = 2C₉CoMnO₉ (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	3.3 ± 1.3	kJ/mol	EqS	Klingler R.J. and Rathke, 1992	solvent: Supercritical carbon dioxide; Temperature range: 353-453 K

2 Dicobalt octacarbonyl (solution) = C₁₂Co₄O₁₂ (solution) + 4 (solution)

By formula: 2C₈Co₂O₈ (solution) = C₁₂Co₄O₁₂ (solution) + 4CO (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	123.4 ± 2.1	kJ/mol	EqS	Bor and Dietler, 1980	solvent: Hexane; Temperature range: 378-418 K

C₁₃H₁₀NaO (solution) + 0.5 Dicobalt octacarbonyl (solution) = C₄CoNaO₄ (solution) + (solution)

By formula: C₁₃H₁₀NaO (solution) + 0.5C₈Co₂O₈ (solution) = C₄CoNaO₄ (solution) + C₁₃H₁₀O (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-157. ± 11.	kJ/mol	RSC	Kiss, Nolan, et al., 1994	solvent: Tetrahydrofuran

Dicobalt octacarbonyl (cr) = 8 (g) + 2 (cr)

By formula: C₈Co₂O₈ (cr) = 8CO (g) + 2Co (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	364.0 ± 8.4	kJ/mol	TD-HFC	Connor, Skinner, et al., 1973	Please also see Pedley and Rylance, 1977.

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Notes

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

Connor, Skinner, et al., 1973
Connor, J.A.; Skinner, H.A.; Virmani, Y., High temperature microcalorimetric studies of the thermal decomposition and iodination of polynuclear carbonyls of Fe, Co, Ru, Rh, Re, Os and Ir, Faraday Symp. Chem. Soc., 1973, 8, 18, https://doi.org/10.1039/fs9730800018 . [all data]

Gardner, Cartner, et al., 1975
Gardner, P.J.; Cartner, A.; Cunninghame, R.G.; Robinson, B.H., J. Chem. Soc., Dalton Trans., 1975, 2582.. [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]

Cardner, Gartner, et al., 1975
Cardner, Peter J.; Gartner, Anthony; Cunninghame, Robert G.; Robinson, Brian H., Bond energies in dicobalt octacarbonyl and bromo- and chloro-methylidynetricobalt enneacarbonyls, J. Chem. Soc., Dalton Trans., 1975, 23, 2582, https://doi.org/10.1039/dt9750002582 . [all data]

Cartner, Robinson, et al., 1973
Cartner, A.; Robinson, B.; Gardner, P.J., J. Chem. Soc., Chem. Commun., 1973, 317.. [all data]

Garner, Chandra, et al., 1995
Garner, M.L.; Chandra, D.; Lau, K.H., Low-temperature vapor pressures of W-, Cr-, and Co-carbonyls, JPE, 1995, 16, 1, 24-29, https://doi.org/10.1007/BF02646245 . [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]

Baev, 1968
Baev, A.K., Vestsi Akad. Navak BSSR, Ser. Khim. Navuk, 1968, 4, 76. [all data]

Cartner, Robinson, et al., 1973, 2
Cartner, Anthony; Robinson, Brian; Gardner, Peter J., Heat of formation of dicobalt octacarbonyl and the metal?carbon monoxide bond strength in carbonyls, J. Chem. Soc., Chem. Commun., 1973, 9, 317b, https://doi.org/10.1039/c3973000317b . [all data]

Rathke, Klingler, et al., 1992
Rathke, J.W.; Klingler, R.J.; Krause, T.R., Organometallics, 1992, 11, 585. [all data]

Bor, 1986
Bor, G., Pure & Appl. Chem., 1986, 58, 543. [all data]

Alemdaroglu, Penninger, et al., 1976
Alemdaroglu, N.H.; Penninger, J.M.L.; Oltay, E., Monatsh. Chem., 1976, 107, 1043. [all data]

Ungváry, 1972
Ungváry, F., J. Organometal. Chem., 1972, 36, 363. [all data]

Connor, 1977
Connor, J.A., Top. Curr. Chem., 1977, 71, 71. [all data]

Pilcher and Skinner, 1982
Pilcher, G.; Skinner, H.A., In The Chemistry of the Metal-Carbon Bond Wiley: New York, Hartley, F. R.; Patai, S., ed(s)., 1982. [all data]

Martinho Simões and Beauchamp, 1990
Martinho Simões, J.A.; Beauchamp, J.L., Chem. Rev., 1990, 90, 629. [all data]

Bidinosti and McIntyre, 1970
Bidinosti, D.R.; McIntyre, N.S., Mass spectrometric study of the thermal decomposition of dimanganese decacarbonyl and dicobalt octacarbonyl, Can. J. Chem., 1970, 48, 593. [all data]

Ungváry and Markó, 1974
Ungváry, F.; Markó, L., J. Organometal. Chem., 1974, 71, 283. [all data]

Kiss, Nolan, et al., 1994
Kiss, G.; Nolan, S.P.; Hoff, C.D., Inorg. Chim. Acta, 1994, 227, 285. [all data]

Klingler R.J. and Rathke, 1992
Klingler R.J.; Rathke, J.W., Inorg. Chem., 1992, 31, 804. [all data]

Bor and Dietler, 1980
Bor, G.; Dietler, U.K., J. Organometal. Chem., 1980, 191, 295. [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]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References

Symbols used in this document:

Δ_fH°_gas	Enthalpy of formation of gas at standard conditions
Δ_fH°_solid	Enthalpy of formation of solid at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions
Δ_rS°	Entropy of reaction at standard conditions
Δ_subH	Enthalpy of sublimation
Δ_subH°	Enthalpy of sublimation at standard conditions

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.