Carbon dioxide

Formula: CO₂
Molecular weight: 44.0095
IUPAC Standard InChI: InChI=1S/CO2/c2-1-3
IUPAC Standard InChIKey: CURLTUGMZLYLDI-UHFFFAOYSA-N
CAS Registry Number: 124-38-9
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.
Isotopologues:
- Carbon dioxide (¹²C¹⁶O₂)
Other names: Carbon oxide (CO2); Carbonic acid, gas; Carbonic anhydride; Dry ice; CO2; Anhydride carbonique; Carbonica; Kohlendioxyd; Kohlensaure; UN 1013; UN 1845; UN 2187; Cardice; Dricold; Drikold; Carbonic acid anhydride; Khladon 744; R 744
Permanent link for this species. Use this link for bookmarking this species for future reference.
Information on this page:
Other data available:
- Phase change data
- Reaction thermochemistry data: reactions 1 to 50, reactions 51 to 100, reactions 101 to 143
- Henry's Law data
- Ion clustering data
- IR Spectrum
- Mass spectrum (electron ionization)
- Gas Chromatography
- Fluid Properties
Data at other public NIST sites:
Options:
- Switch to SI units

Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics data, References, Notes

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-94.051 ± 0.031	kcal/mol	Review	Cox, Wagman, et al., 1984	CODATA Review value
Δ_fH°_gas	-94.054	kcal/mol	Review	Chase, 1998	Data last reviewed in September, 1965
Quantity	Value	Units	Method	Reference	Comment
S°_{gas,1 bar}	51.0958 ± 0.0024	cal/mol*K	Review	Cox, Wagman, et al., 1984	CODATA Review value
S°_{gas,1 bar}	51.097	cal/mol*K	Review	Chase, 1998	Data last reviewed in September, 1965

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Temperature (K)	298. to 1200.	1200. to 6000.
A	5.974511	13.90210
B	13.19000	0.650113
C	-8.052431	-0.117660
D	1.899711	0.009284
E	-0.032657	-1.540941
F	-96.46451	-101.7970
G	54.55141	63.00490
H	-94.05411	-94.05411
Reference	Chase, 1998	Chase, 1998
Comment	Data last reviewed in September, 1965	Data last reviewed in September, 1965

Gas phase ion energetics data

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

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

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

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	13.777 ± 0.001	eV	N/A	N/A	L
Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	129.2	kcal/mol	N/A	Hunter and Lias, 1998	HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	123.3	kcal/mol	N/A	Hunter and Lias, 1998	HL

Electron affinity determinations

EA (eV)	Method	Reference	Comment
-0.599986	EIAE	Knapp, Echt, et al., 1986	Unbound but in -0.3 eV well, from (CO2)n; B
-1.60 ± 0.10	NBIE	Compton, Reinhardt, et al., 1975	B

Ionization energy determinations

IE (eV)	Method	Reference	Comment
13.778 ± 0.002	PE	Wang, Reutt, et al., 1988	LL
13.78	PE	Kimura, Katsumata, et al., 1981	LLK
13.776 ± 0.002	PE	Potts and Fattahallah, 1980	LLK
13. ± 1.	PI	Hitchcock, Brion, et al., 1980	LLK
13.89 ± 0.03	EI	Sahini, Constantin, et al., 1978	LLK
13.79 ± 0.05	EI	Mark and Hille, 1978	LLK
13.77	PI	Jones and Taylor, 1978	LLK
13.777 ± 0.002	PE	Frey, Gotchev, et al., 1977	LLK
13.83 ± 0.05	EI	Bussieres and Marmet, 1977	LLK
13.788	PE	Kronebusch and Berkowitz, 1976	LLK
13.776 ± 0.002	TE	Batten, Taylor, et al., 1976	LLK
13.774 ± 0.003	PI	Parr and Taylor, 1974	LLK
13.9 ± 0.2	EI	Semenov, Volkov, et al., 1973	LLK
13.776 ± 0.008	PI	Parr and Taylor, 1973	LLK
13.78	PE	Natalis, 1973	LLK
13.773 ± 0.002	PI	McCulloh, 1973	LLK
13.80 ± 0.01	PE	Frost, Lee, et al., 1973	LLK
13.788 ± 0.005	PE	Brundle and Turner, 1969	RDSH
13.78 ± 0.01	PE	Eland and Danby, 1968	RDSH
13.77	PE	Spohr and Puttkamer, 1967	RDSH
13.75 ± 0.05	EI	Carette, 1967	RDSH
13.767 ± 0.003	PI	Nakata, Watanabe, et al., 1965	RDSH
13.77 ± 0.03	S	Tanaka, Jursa, et al., 1960	RDSH
13.773	PE	Eland and Berkowitz, 1977	Vertical value; LLK
13.78	PE	Benoit and Harrison, 1977	Vertical value; LLK
13.78	PE	Schweig and Thiel, 1974	Vertical value; LLK
13.79	PE	Potts and Williams, 1974	Vertical value; LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
C⁺	25. ± 2.	O₂	PI	Hitchcock, Brion, et al., 1980	LLK
C⁺	22.7 ± 0.2	O₂	EI	Bussieres and Marmet, 1977	LLK
C⁺	27.8 ± 0.1	2O	EI	Bussieres and Marmet, 1977	LLK
C⁺	24.6 ± 1.0	O₂	EI	Crowe and McConkey, 1974	LLK
C⁺	28.4 ± 0.6	2O	EI	Cuthbert, Farren, et al., 1968	RDSH
C⁺	14.2 ± 0.5	2O	EI	Cuthbert, Farren, et al., 1968	RDSH
C⁺	23.2 ± 0.5	O₂	EI	Cuthbert, Farren, et al., 1968	RDSH
CO⁺	19. ± 2.	O	PI	Hitchcock, Brion, et al., 1980	LLK
CO⁺	19.466	O	PE	Eland and Berkowitz, 1977, 2	LLK
CO⁺	19.42 ± 0.075	O	EI	Bussieres and Marmet, 1977	LLK
CO⁺	19.466	O	PE	Kronebusch and Berkowitz, 1976	LLK
CO⁺	20.9 ± 1.0	O	EI	Crowe and McConkey, 1974	LLK
CO⁺	29.0	O	PI	Samson and Gardner, 1973	LLK
O⁺	19. ± 1.	CO	PI	Hitchcock, Brion, et al., 1980	LLK
O⁺	19.071	CO	PE	Eland and Berkowitz, 1977, 2	LLK
O⁺	19.05 ± 0.05	CO	EI	Bussieres and Marmet, 1977	LLK
O⁺	19.067	CO	PE	Kronebusch and Berkowitz, 1976	LLK
O⁺	19.393 ± 0.008	?	PI	Parr and Taylor, 1974	LLK
O⁺	22.6 ± 1.0	CO	EI	Crowe and McConkey, 1974	LLK
O⁺	19.10 ± 0.01	CO	PI	Dibeler and Walker, 1967	RDSH

References

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Notes

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

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

Knapp, Echt, et al., 1986
Knapp, A.; Echt, O.; Kreisle, D.; Mark, T.D.; Recknagel, E., Formation of Long-Lived CO₂^-, N₂O^- and their Dimer Anions, by Electron Attachment to van der Walls Clusters, Chem. Phys. Lett., 1986, 126, 3-4, 225, https://doi.org/10.1016/S0009-2614(86)80074-4 . [all data]

Compton, Reinhardt, et al., 1975
Compton, R.N.; Reinhardt, P.W.; Cooper, C.D., Collisional ionization of Na, K, and Cs by CO₂, COS, and CS₂: Molecular electron affinities, J. Chem. Phys., 1975, 63, 3821. [all data]

Wang, Reutt, et al., 1988
Wang, L.; Reutt, J.E.; Lee, Y.T.; Shirley, D.A., High resolution UV photoelectron spectroscopy of CO₂, COS, and CS₂ using supersonic molecular beams, J. Electron Spectrosc. Relat. Phenom., 1988, 47, 167. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Potts and Fattahallah, 1980
Potts, A.W.; Fattahallah, G.H., High-resolution ultraviolet photoelectron spectroscopy of CO₂, COS and CS₂, J. Phys. B:, 1980, 13, 2545. [all data]

Hitchcock, Brion, et al., 1980
Hitchcock, A.P.; Brion, C.E.; Van der Wiel, M.J., Absolute oscillator strengths for valence-shell ionic photofragmentation of N₂O and CO₂(8-75 eV), Chem. Phys., 1980, 45, 461. [all data]

Sahini, Constantin, et al., 1978
Sahini, V.E.; Constantin, V.; Serban, I., Determination of ionization potentials using a MI-1305 mass spectrometer, Rev. Roum. Chim., 1978, 23, 479. [all data]

Mark and Hille, 1978
Mark, T.D.; Hille, E., Cross section for single and double ionization of carbon dioxide by electron impact threshold up to 180 eV, J. Chem. Phys., 1978, 69, 2492. [all data]

Jones and Taylor, 1978
Jones, G.G.; Taylor, J.W., A photoionization study of carbon dioxide dimers in a supersonic molecular beam, J. Chem. Phys., 1978, 68, 1768. [all data]

Frey, Gotchev, et al., 1977
Frey, R.; Gotchev, B.; Kalman, O.F.; Peatman, W.B.; Pollak, H.; Schlag, E.W., Photoionization resonance spectra of CO₂⁺ and threshold electron-ion coincidence measurements of the fragmentation of CO₂⁺, Chem. Phys., 1977, 21, 89. [all data]

Bussieres and Marmet, 1977
Bussieres, N.; Marmet, P., Ionization and dissociative ionization of CO₂ by electron impact, Can. J. Phys., 1977, 55, 1889. [all data]

Kronebusch and Berkowitz, 1976
Kronebusch, P.L.; Berkowitz, J., Photodissociative ionization in the 21-41 eV region: O₂, N₂, CO, NO, CO₂, H₂O, NH₃ and CH₄, Int. J. Mass Spectrom. Ion Phys., 1976, 22, 283. [all data]

Batten, Taylor, et al., 1976
Batten, C.F.; Taylor, J.A.; Meisels, G.G., Photoionization processes at threshold. I. Threshold photoelectron and photoionization spectra of CO₂, J. Chem. Phys., 1976, 65, 3316. [all data]

Parr and Taylor, 1974
Parr, G.R.; Taylor, J.W., Photoionization mass spectrometry. IV. Carbon dioxide, Int. J. Mass Spectrom. Ion Phys., 1974, 14, 467. [all data]

Semenov, Volkov, et al., 1973
Semenov, G.A.; Volkov, A.D.; Franktseva, K.E., Mass-spectrometric study of sodium carbonate vaporization, Tr. Leningrad. Tekhnol. Inst. Tsellyul. Bum. Prom., 1973, 30, 153. [all data]

Parr and Taylor, 1973
Parr, G.R.; Taylor, J.W., A photoionization mass spectrometer utilizing a high intensity molecular beam sampling system and synchrotron radiation, Rev. Sci. Instrum., 1973, 44, 1578. [all data]

Natalis, 1973
Natalis, P., Contribution a la spectroscopie photoelectronique. Effets de l'autoionisation dans less spectres photoelectroniques de molecules diatomiques et triatomiques, Acad. R. Belg. Mem. Cl. Sci. Collect. 8, 1973, 41, 1. [all data]

McCulloh, 1973
McCulloh, K.E., Photoionization of carbon dioxide, J. Chem. Phys., 1973, 59, 4250. [all data]

Frost, Lee, et al., 1973
Frost, D.C.; Lee, S.T.; McDowell, C.A., Photoelectron spectra of OCSe, SCSe, and CSe₂, J. Chem. Phys., 1973, 59, 5484. [all data]

Brundle and Turner, 1969
Brundle, C.R.; Turner, D.W., Studies on the photoionisation of the linear triatomic molecules: N₂O, COS, CS₂ and CO₂ using high-resolution photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 195. [all data]

Eland and Danby, 1968
Eland, J.H.D.; Danby, C.J., Photoelectron spectra and ionic structure of carbon dioxide, carbon disulphide and sulphur dioxide, Intern. J. Mass Spectrom. Ion Phys., 1968, 1, 111. [all data]

Spohr and Puttkamer, 1967
Spohr, R.; Puttkamer, E.v., Energiemessung von Photoelektronen und Franck-Condon-Faktoren der Schwingungsubergange einiger Molekulionen, Z. Naturforsch., 1967, 22a, 705. [all data]

Carette, 1967
Carette, J.-D., Ionisation par impact electronique de CO₂ et N₂O, Can. J. Phys., 1967, 45, 2931. [all data]

Nakata, Watanabe, et al., 1965
Nakata, R.S.; Watanabe, K.; Matsunaga, F.M., Absorption and photoionization coefficients of CO₂ in the region 580-1670 A, Sci. Light (Tokyo), 1965, 14, 54. [all data]

Tanaka, Jursa, et al., 1960
Tanaka, Y.; Jursa, A.S.; LeBlanc, F.J., Higher ionization potentials of linear triatomic molecules. I. CO₂, J. Chem. Phys., 1960, 32, 1199. [all data]

Eland and Berkowitz, 1977
Eland, J.H.D.; Berkowitz, J., Photoionization mass spectrometry of HI and DI at high resolution, J. Chem. Phys., 1977, 67, 5034. [all data]

Benoit and Harrison, 1977
Benoit, F.M.; Harrison, A.G., Predictive value of proton affinity. Ionization energy correlations involving oxygenated molecules, J. Am. Chem. Soc., 1977, 99, 3980. [all data]

Schweig and Thiel, 1974
Schweig, A.; Thiel, W., Photoionization cross sections: He I- and He II-photoelectron spectra of homologous oxygen and sulphur compounds, Mol. Phys., 1974, 27, 265. [all data]

Potts and Williams, 1974
Potts, A.W.; Williams, T.A., The observation of "forbidden" transitions in He II photoelectron spectra, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 3. [all data]

Crowe and McConkey, 1974
Crowe, A.; McConkey, J.W., Dissociative ionization by electron impact. III. O⁺, CO⁺ and C⁺ from CO₂, J. Phys. B:, 1974, 7, 349. [all data]

Cuthbert, Farren, et al., 1968
Cuthbert, J.; Farren, J.; PrahalladaRao, B.S.; Preece, E.R., Sequential mass spectrometry. III. Ions and fragments from carbon dioxide anddisulphide, J. Phys. B:, 1968, 1, 62. [all data]

Eland and Berkowitz, 1977, 2
Eland, J.H.D.; Berkowitz, J., Formation and predissociation of CO₂⁺(C²Σ⁺_g), J. Chem. Phys., 1977, 67, 2782. [all data]

Samson and Gardner, 1973
Samson, J.A.R.; Gardner, J.L., Fluorescence excitation and photoelectron spectra of CO₂ induced by vacuum ultraviolet radiation between 185 and 716 angstroms, J. Geophys. Res., 1973, 78, 3663. [all data]

Dibeler and Walker, 1967
Dibeler, V.H.; Walker, J.A., Mass spectrometric study of the photoionization of small polyatomic molecules, Advan. Mass Spectrom., 1967, 4, 767. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References

Symbols used in this document:

AE	Appearance energy
EA	Electron affinity
IE (evaluated)	Recommended ionization energy
S°_{gas,1 bar}	Entropy of gas at standard conditions (1 bar)
Δ_fH°_gas	Enthalpy of formation of gas 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.