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calcium oxide

Gas phase ion energetics data

Go To: Top, 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.

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
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
IE (evaluated)6.66 ± 0.18eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)1190.6kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity1162.3kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
6.66 ± 0.18END/DERDalleska and Armentrout, 1994LL
6.5 ± 0.3EVALBelyaev, Gotkis, et al., 1990LL
7. ± 1.EIFarber, Srivastava, et al., 1987LBLHLM
6.9 ± 0.15DERMurad, 1983LBLHLM
7. ± 1.EIFarber and Srivastava, 1976LLK
6.5EIDrowart, Exsteen, et al., 1964RDSH

Constants of diatomic molecules

Go To: Top, Gas phase ion energetics 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

Symbols used in the table of constants
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)
Diatomic constants for 40Ca16O
Progression of absorption bands (DeltaG ~ 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 rarrow 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 1Sigma+ 28857.8 560.9 Z 4.0  0.3731 1 0.0032  (0.0000007)  1.989 C lrarrow x 2 R 28772.4 Z
missing citation; Veits and Gurvich, 1967
B 1Pi 25991 [574.4] Z   0.3882 3 1 0.0055  (0.0000007)  1.950 B lrarrow X 4 R 25913.0 Z
Lagerqvist, 1954; Veits and Gurvich, 1967
A 1Sigma+ 11554.8 718.9 Z 2.11  0.40592 5 0.00137  5.4  1.9067 A rarrow X R 11548.84 Z
missing citation; missing citation; Brewer and Hauge, 1968; Field, 1974
A' 1Pi 8433 545.7 H 2.54  0.337 0.0021    2.093 A' rarrow X 6 R 8340
missing citation
a 3Pii (8313) 7 556 3.3  0.335     2.099  
X 1Sigma+ 0 732.11 Z 4.81 8  0.44452   6.58 9  1.8221 10 


2xi system of Lejeune and Rosen, 1945.
3Value of BQ; BPR - BQ = +0.0005.
4eta system of Lejeune and Rosen, 1945.
5Many rotational perturbations by A' 1Pi and a 3Pii Hultin and Lagerqvist, 1951, Field, 1974.
6Directly observed for v' > 9 only; vibrational numbering determined from the perturbations in A 1Sigma+ Field, 1974.
7A = -58, from perturbations in A 1Sigma+ as are the other constants for this state; see Field, 1974.
8The vibrational constants in the Table are derived from levels with v leq 4 Hultin and Lagerqvist, 1951, Lagerqvist, 1954. From band heads in the A-X system (v" leq 13) and accounting for head-origin separations, Brewer and Hauge, 1968 have derived omegae= 733.4 Brewer and Hauge, 1968, omegaexe= 5.28 Brewer and Hauge, 1968.
9missing note
10The 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 1Sigma ground state properties see Yoshimine, 1968.
11From 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 1Sigma ground state - lead to D00 = 4.04 eV Kalff and Alkemade, 1973.


Go To: Top, Gas phase ion energetics 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.

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]

Dalleska and Armentrout, 1994
Dalleska, N.F.; Armentrout, P.B., Guided ion beam studies of reactions of alkaline earth ions with O2, Int. J. Mass Spectrom. Ion Processes, 1994, 134, 203. [all data]

Belyaev, Gotkis, et al., 1990
Belyaev, V.N.; Gotkis, I.S.; Lebedeva, N.L.; Krasnov, K.S., Ionization potentials of MX molecules (M = Ca, Sr, Ba; X = F, Cl, Br, I, OH, O), Russ. J. Phys. Chem., 1990, 64, 773. [all data]

Farber, Srivastava, et al., 1987
Farber, M.; Srivastava, R.D.; Moyer, J.W.; Leeper, J.D., Effusion mass spectrometric determination of thermodynamic properties of the gaseous mono- and di-hydroxides of calcium and KCaO(g), J. Chem. Soc. Faraday Trans. 2, 1987, 83, 3229. [all data]

Murad, 1983
Murad, E., Abstraction reactions of Ca+ and Sr+ ions, J. Chem. Phys., 1983, 78, 6611. [all data]

Farber and Srivastava, 1976
Farber, M.; Srivastava, R.D., The dissociation energies of calcium oxide and strontium oxide, High Temp. Sci., 1976, 8, 73. [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]

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 3«PI» and 1«PI» 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]

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]


Go To: Top, Gas phase ion energetics data, Constants of diatomic molecules, References