calcium oxide
- Formula: CaO
- Molecular weight: 56.077
- IUPAC Standard InChI: InChI=1S/Ca.O
- IUPAC Standard InChIKey: ODINCKMPIJJUCX-UHFFFAOYSA-N
- CAS Registry Number: 1305-78-8
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: Calcium monoxide
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Constants of diatomic molecules, References, Notes
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 |
|---|---|---|---|---|---|
| ΔfH°gas | 10.50 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas,1 bar | 52.512 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1973 |
Gas 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) | 4500. to 6000. |
|---|---|
| A | 85.57620 |
| B | -28.20000 |
| C | 3.986480 |
| D | -0.198946 |
| E | -147.0110 |
| F | -170.5960 |
| G | 41.22770 |
| H | 10.50000 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in June, 1973 |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, Constants of diatomic molecules, References, Notes
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 |
|---|---|---|---|---|---|
| ΔfH°liquid | -133.21 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°liquid,1 bar | 14.89 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔfH°solid | -151.75 ± 0.22 | kcal/mol | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
| ΔfH°solid | -151.79 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid,1 bar | 9.11 ± 0.1 | cal/mol*K | Review | Cox, Wagman, et al., 1984 | CODATA Review value |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid | 9.128 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1973 |
Liquid 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) | 3200. to 4500. |
|---|---|
| A | 15.00000 |
| B | 1.106521×10-7 |
| C | -2.610032×10-8 |
| D | 2.143000×10-9 |
| E | 1.554651×10-7 |
| F | -141.4450 |
| G | 27.93760 |
| H | -133.2060 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in June, 1973 |
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. to 3200. |
|---|---|
| A | 11.93930 |
| B | 1.168240 |
| C | -0.084144 |
| D | 0.011039 |
| E | -0.197203 |
| F | -156.0640 |
| G | 22.12260 |
| H | -151.7900 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in June, 1973 |
Constants of diatomic molecules
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: Klaus P. Huber and Gerhard H. Herzberg
Data collected through September, 1976
| Symbol | Meaning |
|---|---|
| State | electronic state and / or symmetry symbol |
| Te | minimum electronic energy (cm-1) |
| ωe | vibrational constant – first term (cm-1) |
| ωexe | vibrational constant – second term (cm-1) |
| ωeye | vibrational constant – third term (cm-1) |
| Be | rotational constant in equilibrium position (cm-1) |
| αe | rotational constant – first term (cm-1) |
| γe | rotation-vibration interaction constant (cm-1) |
| De | centrifugal distortion constant (cm-1) |
| βe | rotational constant – first term, centrifugal force (cm-1) |
| re | internuclear distance (Å) |
| Trans. | observed transition(s) corresponding to electronic state |
| ν00 | position of 0-0 band (units noted in table) |
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Progression of absorption bands (ΔG ~ 850) in Kr and Xe matrices, 20000 - 26000 cm-1; observed for both Ca16O and Ca18O, but not definitely assigned. | ||||||||||||
| ↳Brewer and Wang, 1972 | ||||||||||||
| (B → A') | ||||||||||||
| ↳Lejeune, 1945; Gaydon, 1955; missing citation; Volnyets, Kovalenok, et al., 1974 | ||||||||||||
| Orange system of strong emission bands, 15700 - 16700 cm-1; no analysis. | ||||||||||||
| ↳Lejeune, 1945; Gaydon, 1955; missing citation; missing citation | ||||||||||||
| C 1Σ+ | 28857.8 | 560.9 Z | 4.0 | 0.3731 1 | 0.0032 | (0.0000007) | 1.989 | C ↔ x 2 R | 28772.4 Z | |||
| ↳missing citation; Veits and Gurvich, 1967 | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| B 1Π | 25991 | [574.4] Z | 0.3882 3 1 | 0.0055 | (0.0000007) | 1.950 | B ↔ X 4 R | 25913.0 Z | ||||
| ↳Lagerqvist, 1954; Veits and Gurvich, 1967 | ||||||||||||
| A 1Σ+ | 11554.8 | 718.9 Z | 2.11 | 0.40592 5 | 0.00137 | 5.4 | 1.9067 | A → X R | 11548.84 Z | |||
| ↳missing citation; missing citation; Brewer and Hauge, 1968; Field, 1974 | ||||||||||||
| A' 1Π | 8433 | 545.7 H | 2.54 | 0.337 | 0.0021 | 2.093 | A' → X 6 R | 8340 | ||||
| ↳missing citation | ||||||||||||
| a 3Πi | (8313) 7 | 556 | 3.3 | 0.335 | 2.099 | |||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| X 1Σ+ | 0 | 732.11 Z | 4.81 8 | 0.44452 | 6.58 9 | 1.8221 | 10 | |||||
Notes
| 1 | Perturbations. |
| 2 | ξ system of Lejeune and Rosen, 1945. |
| 3 | Value of BQ; BPR - BQ = +0.0005. |
| 4 | η system of Lejeune and Rosen, 1945. |
| 5 | Many rotational perturbations by A' 1Π and a 3Πi Hultin and Lagerqvist, 1951, Field, 1974. |
| 6 | Directly observed for v' > 9 only; vibrational numbering determined from the perturbations in A 1Σ+ Field, 1974. |
| 7 | A = -58, from perturbations in A 1Σ+ as are the other constants for this state; see Field, 1974. |
| 8 | The vibrational constants in the Table are derived from levels with v ≤ 4 Hultin and Lagerqvist, 1951, Lagerqvist, 1954. From band heads in the A-X system (v" ≤ 13) and accounting for head-origin separations, Brewer and Hauge, 1968 have derived ωe= 733.4 Brewer and Hauge, 1968, ωexe= 5.28 Brewer and Hauge, 1968. |
| 9 | missing note |
| 10 | The question whether this is the ground state was for long in doubt but the observation by Ault and Andrews, 1975 of a fundamental frequency of 707 cm-1 in a nitrogen matrix seems to settle it: see also Field, 1974 and the theoretical work of Carlson, Kaiser, et al., 1970. For computed 1Σ ground state properties see Yoshimine, 1968. |
| 11 | From the Ca + ClO2 chemiluminescence spectrum Engelke, Sander, et al., 1976. By contrast, the most recent mass-spectrometric Colin, Goldfinger, et al., 1964, Drowart, Exsteen, et al., 1964 and flame-photometric Kalff and Alkemade, 1973 determinations - corrected, where necessary, for a 1Σ ground state - lead to D00 = 4.04 eV Kalff and Alkemade, 1973. |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Constants of diatomic molecules, 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]
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]
Brewer and Wang, 1972
Brewer, L.; Wang, J.L.-F.,
Ground state of gaseous CaO; a study of the matrix spectra of Ca and CaO,
J. Chem. Phys., 1972, 56, 4305. [all data]
Lejeune, 1945
Lejeune, J.-M.,
Application de la methode d'explosion de fils minces a l'etude du spectre de CaO,
Bull. Soc. R. Sci. Liege, 1945, 14, 318. [all data]
Gaydon, 1955
Gaydon, A.G.,
Green and orange band spectra of CaOH, CaOD and calcium oxide,
Proc. R. Soc. London A, 1955, 231, 437. [all data]
Volnyets, Kovalenok, et al., 1974
Volnyets, G.A.; Kovalenok, G.V.; Sokolov, V.A.,
Rotational structure of the 5472-5463 Å band of calcium oxide,
Opt. Spectrosc. Engl. Transl., 1974, 36, 609, In original 1034. [all data]
Veits and Gurvich, 1967
Veits, I.V.; Gurvich, L.V.,
Investigation of the absorption spectra of molecules of difficulty volatile substances and radicals in shock waves,
Dokl. Chem. Engl. Transl., 1967, 173, 377, In original 1325. [all data]
Lagerqvist, 1954
Lagerqvist, A.,
Ultra-violet and blue bands of calcium oxide,
Ark. Fys., 1954, 8, 83. [all data]
Brewer and Hauge, 1968
Brewer, L.; Hauge, R.,
Near infrared bands of diatomic CaO and SrO,
J. Mol. Spectrosc., 1968, 25, 330. [all data]
Field, 1974
Field, R.W.,
Assignment of the lowest 3Π and 1Π states of CaO, SrO, and BaO,
J. Chem. Phys., 1974, 60, 2400. [all data]
Lejeune and Rosen, 1945
Lejeune, J.-M.; Rosen, B.,
Contribution a l'etude du spectre de CaO,
Bull. Soc. R. Sci. Liege, 1945, 14, 322. [all data]
Hultin and Lagerqvist, 1951
Hultin, M.; Lagerqvist, A.,
An infra-red band-system of calcium oxide,
Ark. Fys., 1951, 2, 471. [all data]
Ault and Andrews, 1975
Ault, B.S.; Andrews, L.,
Nitrogen matrix reactions of alkaline earth metal atoms with ozone: infrared spectra of the alkaline earth metal oxide molecules,
J. Chem. Phys., 1975, 62, 2320. [all data]
Carlson, Kaiser, et al., 1970
Carlson, K.D.; Kaiser, K.; Moser, C.; Wahl, A.C.,
Electronic structure and low-lying triplet states of CaO,
J. Chem. Phys., 1970, 52, 4678. [all data]
Yoshimine, 1968
Yoshimine, Y.,
Computed ground state properties of BeO, MgO, CaO, and SrO in molecular orbital approximation,
J. Phys. Soc. Jpn., 1968, 25, 1100. [all data]
Engelke, Sander, et al., 1976
Engelke, F.; Sander, R.K.; Zare, R.N.,
Crossed-beam chemiluminescent studies of alkaline earth atoms with ClO2,
J. Chem. Phys., 1976, 65, 1146. [all data]
Colin, Goldfinger, et al., 1964
Colin, R.; Goldfinger, P.; Jeunehomme, M.,
Mass-spectrometric studies of vaporization of the sulphides of calcium, strontium and barium. The dissociation energy of S2 and SO,
Trans. Faraday Soc., 1964, 60, 306. [all data]
Drowart, Exsteen, et al., 1964
Drowart, J.; Exsteen, G.; Verhaegen, G.,
Mass spectrometric determination of the dissociation energy of the molecules MgO, CaO, SrO and Sr2O,
J. Chem. Soc. Faraday Trans., 1964, 60, 1920. [all data]
Kalff and Alkemade, 1973
Kalff, P.J.; Alkemade, C.T.J.,
Determination of dissociation energies for some alkaline earth (hydro-) oxides in CO/N2O flames,
J. Chem. Phys., 1973, 59, 2572. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Constants of diatomic molecules, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) S°liquid,1 bar Entropy of liquid at standard conditions (1 bar) S°solid Entropy of solid at standard conditions S°solid,1 bar Entropy of solid at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions ΔfH°liquid Enthalpy of formation of liquid at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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