Molybdenum hexacarbonyl

Formula: C₆MoO₆
Molecular weight: 264.02
IUPAC Standard InChI: InChI=1S/6CO.Mo/c6*1-2;
IUPAC Standard InChIKey: KMKBZNSIJQWHJA-UHFFFAOYSA-N
CAS Registry Number: 13939-06-5
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.
Other names: Molybdenum carbonyl (Mo(CO)6), (OC-6-11)-; Molybdenum carbonyl (Mo(CO)6); Hexacarbonyl molybdenum; Mo(CO)6; Molybdenum carbonyl
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Gas phase thermochemistry data

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Data compiled by: José A. Martinho Simões

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-908.5 ± 2.9	kJ/mol	Review	Martinho Simões
Δ_fH°_gas	-886.5 ± 4.4	kJ/mol	Review	Martinho Simões
Δ_fH°_gas	-916.1 ± 4.4	kJ/mol	Review	Martinho Simões
Δ_fH°_gas	-915.3 ± 2.1	kJ/mol	Review	Martinho Simões	Selected data.

Reaction thermochemistry data

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Data compiled as indicated in comments:
MS - José A. Martinho Simões
B - 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

Molybdenum hexacarbonyl (solution) = C₅MoO₅ (solution) + (solution)

By formula: C₆MoO₆ (solution) = C₅MoO₅ (solution) + CO (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	132.6 ± 5.9	kJ/mol	KinS	Graham and Angelici, 1967	solvent: Decalin; The reaction enthalpy and entropy were identified with the enthalpy and entropy of activation for the reaction of Mo(CO)6(solution) with PBu3(solution).; MS
Δ_rH°	126.4	kJ/mol	KinS	Werner and Prinz, 1966	solvent: n-Decane+cyclohexane mixture; The reaction enthalpy and entropy were identified with the enthalpy and entropy of activation for the reactions of Mo(CO)6(solution) with a phosphine and an amine. The results were quoted from Graham and Angelici, 1967.; MS

Molybdenum hexacarbonyl (g) = C₅MoO₅ (g) + (g)

By formula: C₆MoO₆ (g) = C₅MoO₅ (g) + CO (g)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	146. ± 21.	kJ/mol	KinG	Ganske and Rosenfeld, 1990	MS
Δ_rH°	170. ± 13.	kJ/mol	LPHP	Lewis, Golden, et al., 1984	The reaction enthalpy at 298 K relies on an activation energy of 163.2 kJ/mol and assumes a negligible activation barrier for product recombination. The enthalpy of formation relies on -915.3 ± 2.1 kJ/mol for the enthalpy of formation of Mo(CO)6(g); MS
Δ_rH°	126.4	kJ/mol	KinG	Cetini and Gambino, 1963	Please also see Graham and Angelici, 1967. The reaction enthalpy and entropy were identified with the enthalpy and entropy of activation for the reaction of Mo(CO)6(g) with CO(g) Cetini and Gambino, 1963. The results were quoted from Graham and Angelici, 1967.; MS

Molybdenum hexacarbonyl (solution) + (solution) = C₁₂H₁₆MoO₅ (solution) + (solution)

By formula: C₆MoO₆ (solution) + C₇H₁₆ (solution) = C₁₂H₁₆MoO₅ (solution) + CO (solution)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	135. ± 12.	kJ/mol	PAC	Johnson, Popov, et al., 1991	solvent: Heptane; The reaction enthalpy relies on 0.67 for the quantum yield of CO dissociation.; MS
Δ_rH°	133.1 ± 5.4	kJ/mol	PAC	Morse, Parker, et al., 1989	solvent: Heptane; The reaction enthalpy relies on 0.67 for the quantum yield of CO dissociation; MS

Molybdenum hexacarbonyl (cr) = 6 (g) + (cr)

By formula: C₆MoO₆ (cr) = 6CO (g) + Mo (cr)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	325.9 ± 1.5	kJ/mol	TD-HZC	Barnes, Pilcher, et al., 1974	Please also see Pedley and Rylance, 1977 and Tel'noi and Rabinovich, 1977.; MS
Δ_rH°	297.1 ± 4.2	kJ/mol	TD-HFC	Connor, Skinner, et al., 1972	Please also see Pedley and Rylance, 1977 and Tel'noi and Rabinovich, 1977.; MS

+ Molybdenum hexacarbonyl = ( • )

By formula: H^- + C₆MoO₆ = (H^- • C₆MoO₆)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	184. ± 17.	kJ/mol	N/A	Lane and Squires, 1988	gas phase; Hydride affinity between CH2=O and PhCH=O; B

Molybdenum hexacarbonyl (cr) + 3 (g) = C₁₈H₁₅MoN₃O₃ (cr) + 3 (g)

By formula: C₆MoO₆ (cr) + 3C₄H₄N₂ (g) = C₁₈H₁₅MoN₃O₃ (cr) + 3CO (g)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	-50.4 ± 7.0	kJ/mol	HFC	Adedeji, Connor, et al., 1978	MS

C₁₀H₅MoNO₅ (cr) + (g) = Molybdenum hexacarbonyl (g) + (g)

By formula: C₁₀H₅MoNO₅ (cr) + CO (g) = C₆MoO₆ (g) + C₄H₄N₂ (g)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	57. ± 3.	kJ/mol	DSC	Daamen, van der Poel, et al., 1979	MS

Molybdenum hexacarbonyl (g) = C₃MoO₃ (g) + 3 (g)

By formula: C₆MoO₆ (g) = C₃MoO₃ (g) + 3CO (g)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	439. ± 42.	kJ/mol	MBPS	Venkataraman, Hou, et al., 1990	MS

Gas phase ion energetics data

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Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias

Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	762.6	kJ/mol	N/A	Hunter and Lias, 1998	HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	738.1	kJ/mol	N/A	Hunter and Lias, 1998	HL

Ionization energy determinations

IE (eV)	Method	Reference	Comment
8.25	PE	Cooper, Green, et al., 1987	LBLHLM
8.2	PE	Hubbard and Lichtenberger, 1982	LBLHLM
8.46 ± 0.01	EI	Michels, Flesch, et al., 1980	LLK
8.50 ± 0.05	EI	Paetzold and Abd-el-Mottaleb, 1975	LLK
8.227 ± 0.011	PI	Lloyd and Schlag, 1969	RDSH
8.43 ± 0.05	EI	Junk and Svec, 1968	RDSH
8.46 ± 0.08	EI	Bidinosti and McIntyre, 1967	RDSH
8.23 ± 0.12	EI	Winters and Kiser, 1965	RDSH
8.30 ± 0.03	EI	Foffani, Pignataro, et al., 1965	RDSH
8.12 ± 0.03	PI	Vilesov and Kurbatov, 1961	RDSH
8.45	PE	Hubbard and Lichtenberger, 1982	Vertical value; LBLHLM
8.50	PE	Head, Nixon, et al., 1975	Vertical value; LLK
8.50 ± 0.02	PE	Higginson, Lloyd, et al., 1973	Vertical value; LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
MoC⁺	24. ± 1.	?	EI	Bidinosti and McIntyre, 1967	RDSH
MoC⁺	27.2 ± 0.4	?	EI	Winters and Kiser, 1965	RDSH
CMoO⁺	16.52 ± 0.03	5CO	EI	Michels, Flesch, et al., 1980	LLK
MoCO⁺	15.61	5CO	EI	Junk and Svec, 1968	RDSH
MoCO⁺	15.7 ± 0.2	5CO	EI	Bidinosti and McIntyre, 1967	RDSH
MoCO⁺	18.1 ± 0.3	5CO	EI	Winters and Kiser, 1965	RDSH
MoCO⁺	15.8 ± 0.06	5CO	EI	Foffani, Pignataro, et al., 1965	RDSH
C₂MoO₂⁺	14.86 ± 0.02	4CO	EI	Michels, Flesch, et al., 1980	LLK
MoC₂O₂⁺	14.76	4CO	EI	Junk and Svec, 1968	RDSH
MoC₂O₂⁺	14.5 ± 0.1	4CO	EI	Bidinosti and McIntyre, 1967	RDSH
MoC₂O₂⁺	15.6 ± 0.3	4CO	EI	Winters and Kiser, 1965	RDSH
MoC₂O₂⁺	13.9 ± 0.3	4CO	EI	Foffani, Pignataro, et al., 1965	RDSH
C₃MoO₃⁺	13.29 ± 0.02	3CO	EI	Michels, Flesch, et al., 1980	LLK
MoC₃O₃⁺	13.18	3CO	EI	Junk and Svec, 1968	RDSH
MoC₃O₃⁺	12.8 ± 0.1	3CO	EI	Bidinosti and McIntyre, 1967	RDSH
MOC₃O₃⁺	13.7 ± 0.3	3CO	EI	Winters and Kiser, 1965	RDSH
MoC₃O₃⁺	12.36 ± 0.12	3CO	EI	Foffani, Pignataro, et al., 1965	RDSH
C₄MoO₄⁺	11.61 ± 0.02	2CO	EI	Michels, Flesch, et al., 1980	LLK
MoC₄O₄⁺	10.72	2CO	EI	Junk and Svec, 1968	RDSH
MoC₄O₄⁺	10.63 ± 0.15	2CO	EI	Bidinosti and McIntyre, 1967	RDSH
MoC₄O₄⁺	11.9 ± 0.2	2CO	EI	Winters and Kiser, 1965	RDSH
MoC₄O₄⁺	11.28 ± 0.14	2CO	EI	Foffani, Pignataro, et al., 1965	RDSH
C₅MoO₅⁺	10.02 ± 0.02	CO	EI	Michels, Flesch, et al., 1980	LLK
MoC₅O₅⁺	9.14	CO	EI	Junk and Svec, 1968	RDSH
MoC₅O₅⁺	9.4 ± 0.1	CO	EI	Bidinosti and McIntyre, 1967	RDSH
MoC₅O₅⁺	9.80 ± 0.15	CO	EI	Winters and Kiser, 1965	RDSH
MoC₅O₅⁺	9.64 ± 0.05	CO	EI	Foffani, Pignataro, et al., 1965	RDSH
Mo⁺	18.24 ± 0.06	6CO	EI	Michels, Flesch, et al., 1980	LLK
Mo⁺	19.63	6CO	EI	Junk and Svec, 1968	RDSH
Mo⁺	18.6 ± 0.2	6CO	EI	Bidinosti and McIntyre, 1967	RDSH
Mo⁺	20.7 ± 0.5	6CO	EI	Winters and Kiser, 1965	RDSH
Mo⁺	18.3 ± 0.3	6CO	EI	Foffani, Pignataro, et al., 1965	RDSH
MoO⁺	24. ± 1.	?	EI	Bidinosti and McIntyre, 1967	RDSH

Ion clustering data

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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. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

+ Molybdenum hexacarbonyl = ( • )

By formula: H^- + C₆MoO₆ = (H^- • C₆MoO₆)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	184. ± 17.	kJ/mol	N/A	Lane and Squires, 1988	gas phase; Hydride affinity between CH2=O and PhCH=O

References

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

Graham and Angelici, 1967
Graham, J.R.; Angelici, R.J., Inorg. Chem., 1967, 6, 2082. [all data]

Werner and Prinz, 1966
Werner, H.; Prinz, R., Chem. Ber., 1966, 99, 3582. [all data]

Ganske and Rosenfeld, 1990
Ganske, J.A.; Rosenfeld, R.N., J. Phys. Chem., 1990, 94, 4315. [all data]

Lewis, Golden, et al., 1984
Lewis, K.E.; Golden, D.M.; Smith, G.P., Organometallic bond dissociation energies: Laser pyrolysis of Fe(CO)₅, Cr(CO)₆, Mo(CO)₆, and W(CO)₆, J. Am. Chem. Soc., 1984, 106, 3905. [all data]

Cetini and Gambino, 1963
Cetini, G.; Gambino, O., Atti Accad. Sci. Torino, Classe Sci. Fis. Mat. Nat., 1963, 97, 757. [all data]

Johnson, Popov, et al., 1991
Johnson, F.P.A.; Popov, V.K.; George, M.W.; Bagratashvili, V.N.; Poliakoff, M.; Turner, J.J., Mendeleev Commun., 1991, 145.. [all data]

Morse, Parker, et al., 1989
Morse, J.M., Jr.; Parker, G.H.; Burkey, T.J., Organometallics, 1989, 8, 2471. [all data]

Barnes, Pilcher, et al., 1974
Barnes, D.S.; Pilcher, G.; Pittam, D.A.; Skinner, H.A.; Todd, D.; Virmani, Y., J. Less-Common Met., 1974, 36, 177. [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]

Tel'noi and Rabinovich, 1977
Tel'noi, V.I.; Rabinovich, I.B., Russ. Chem. Rev., 1977, 46, 689. [all data]

Connor, Skinner, et al., 1972
Connor, J.A.; Skinner, H.A.; Virmani, Y., Microcalorimetric studies. Thermal decomposition and iodination of metal carbonyls, J. Chem. Soc., Faraday Trans. 1, 1972, 68, 0, 1754, https://doi.org/10.1039/f19726801754 . [all data]

Lane and Squires, 1988
Lane, K.R.; Squires, R.R., Hydride Transfer to Transition Metal Carbonyls in the Gas Phase. Formation and Relative Stabilities of Anionic Formyl Complexes, Polyhedron, 1988, 7, 16-17, 1609, https://doi.org/10.1016/S0277-5387(00)81786-6 . [all data]

Adedeji, Connor, et al., 1978
Adedeji, F.A.; Connor, J.A.; Demain, C.P.; Martinho Simões, J.A.; Skinner, H.A.; Zafarani- Moattar, M.T., J. Organometal. Chem., 1978, 149, 333. [all data]

Daamen, van der Poel, et al., 1979
Daamen, H.; van der Poel, H.; Stufkens, D.J.; Oskam, A., Thermochim. Acta, 1979, 34, 69. [all data]

Venkataraman, Hou, et al., 1990
Venkataraman, B.; Hou, H.; Zhang, Z.; Chen, S.; Bandukwalla, G.; Vernon, M., J. Chem. Phys., 1990, 92, 5338. [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]

Cooper, Green, et al., 1987
Cooper, G.; Green, J.C.; Payne, M.; Dobson, B.R.; Hillier, I.H., Photoelectron spectroscopy with variable photon energy: A study of the metal hexacarbonyls, M(CO)₆, Where M = CR, MO, and W., J. Am. Chem. Soc., 1987, 109, 3836. [all data]

Hubbard and Lichtenberger, 1982
Hubbard, J.L.; Lichtenberger, D.L., Vibrational fine structure in the valence ionizations of transition-metal hexacarbonyls: New experimental indication of metal-to-carbonyl π bonding, J. Am. Chem. Soc., 1982, 104, 2132. [all data]

Michels, Flesch, et al., 1980
Michels, G.D.; Flesch, G.D.; Svec, H.J., Comparative mass spectrometry of the group 6B hexacarbonyls and pentacarbonyl thiocarbonyls, Inorg. Chem., 1980, 19, 479. [all data]

Paetzold and Abd-el-Mottaleb, 1975
Paetzold, R.; Abd-el-Mottaleb, S., Correlative studies of some spectroscopic and bonding parameters in octahedrally coordinated metal carbonyl complexes, J. Mol. Struct., 1975, 24, 357. [all data]

Lloyd and Schlag, 1969
Lloyd, D.R.; Schlag, E.W., Photoionization studies of metal carbonyls. I. Ionization potentials and the bonding in group VI metal hexacarbonyls and in mononuclear carbonyls and nitrosyl carbonyls of iron, cobalt, and nickel, Inorg. Chem., 1969, 8, 2544. [all data]

Junk and Svec, 1968
Junk, G.A.; Svec, H.J., Energetics of the ionization and dissociation of Ni(CO)₄, Fe(CO)₅, Cr(CO)₆, Mo(CO)₆ and W(CO)₆, Z. Naturforsch., 1968, 23b, 1. [all data]

Bidinosti and McIntyre, 1967
Bidinosti, D.R.; McIntyre, N.S., Electron-impact study of some binary metal carbonyls, Can. J. Chem., 1967, 45, 641. [all data]

Winters and Kiser, 1965
Winters, R.E.; Kiser, R.W., Mass spectrometric studies of chromium, molybdenum, and tungsten hexacarbonyls, Inorg. Chem., 1965, 4, 157. [all data]

Foffani, Pignataro, et al., 1965
Foffani, A.; Pignataro, S.; Cantone, B.; Grasso, F., Mass spectra of metal hexacarbonyls, Z. Physik. Chem. (Frankfurt), 1965, 45, 79. [all data]

Vilesov and Kurbatov, 1961
Vilesov, F.I.; Kurbatov, B.L., Photoionization of esters and metal carbonyis in the gaseous phase, Dokl. Akad. Nauk SSSR, 1961, 140, 1364, In original 792. [all data]

Head, Nixon, et al., 1975
Head, R.A.; Nixon, J.F.; Sharp, G.J.; Clark, R.J., Photoelectron spectroscopic study of metal trifluorophosphine and hydridotrifluorophosphine complexes, J. Chem. Soc. Dalton Trans., 1975, 2054. [all data]

Higginson, Lloyd, et al., 1973
Higginson, B.R.; Lloyd, D.R.; Burroughs, P.; Gibson, D.M.; Orchard, A.F., Photoelectron studies of metal carbonyls. Part 2. The valence region photoelectron spectra of the Group VIA hexacarbonyls, J. Chem. Soc. Faraday Trans. 2, 1973, 1659. [all data]

Notes

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Symbols used in this document:

AE Appearance energy

Δ_fH°_gas Enthalpy of formation of gas at standard conditions

Δ_rH° Enthalpy of reaction at standard conditions

Δ_rS° Entropy of reaction at standard conditions
Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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AE	Appearance energy
Δ_fH°_gas	Enthalpy of formation of gas at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions
Δ_rS°	Entropy of reaction at standard conditions