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Gas phase thermochemistry 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.

Quantity Value Units Method Reference Comment
Deltafgas36.60kJ/molReviewChase, 1998Data last reviewed in June, 1977
Quantity Value Units Method Reference Comment
gas,1 bar189.65J/mol*KReviewChase, 1998Data last reviewed in June, 1977

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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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Temperature (K) 298. - 1500.1500. - 6000.
A 28.9693534.24939
B -3.6579461.992422
C 10.53573-0.305116
D -3.7495720.020965
E 0.114832-4.534912
F 28.4269718.46985
G 226.0126222.3135
H 36.6020536.60205
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in June, 1977 Data last reviewed in June, 1977

Constants of diatomic molecules

Go To: Top, Gas 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 May, 1977

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 16O2H
C 2Sigma+ (89470) (898) (10)  [2.235] 1     [2.053] C rarrow A 2 3 R 56090.3 Z
Felenbok, 1963; missing citation
C 2Sigma+ 4           (C rarrow X) 2 (88568)
missing citation
D 2Sigma- (82160) (2074)   [8.2283] 5   [5.179E-4]  [1.07018] D larrow X R 81853.22 6 Z
Douglas, 1974
B 2Sigma+ 69775 [546.9] Z 7  [2.745] 8 9  [2.50E-4] 10  [1.8529] B rarrow A 11 R 36275.7 Z
Barrow, 1956; Herman, Felenbok, et al., 1961; missing citation; Czarny and Felenbok, 1968; missing citation
A 2Sigma+ 32680.85 12 2316.17 Z 50.433 13 -0.2350 9.1936 14 15 16 17 0.3181 18 -0.00119 [5.763E-4] 19  1.0124 A lrarrow X 20 21 R 32477.18 6 Z
missing citation; Clyne, Coxon, et al., 1973; Coxon, 1975
X 2Pii 0 22 2720.24 Z 44.055  10.0209 23 17 0.2757 24 .0006 [5.374E-4] 25  0.96975 26  
Dousmanis, Sanders, et al., 1955; Meerts and Dymanus, 1973; Meerts and Dymanus, 1975
ESR sp. 27
Carrington and Lucas, 1970


1Spin splitting constant gamma0 = +0.6.
2Lifetimes of 6.1 and ~2 ns have been reported Smith and Stella, 1975 for the upper state of the CrarrowA bands and for the 1850 group, respectively. See 3 of O1H.
3Only the 0-11 and 0-12 bands have been observed Carlone and Dalby, 1969.
4Strong many-line spectrum 1900-1700 Å, tentative identification.
5Spin splitting constant gamma0 = -0.156.
6See note h of O1H.
7DeltaG(3/2) = 357.9 Carlone and Dalby, 1969. Using isotope relations Barrow, 1956 derives omegae = 684, omegaexe = 55.7, omegaeye = -8.3.
8Spin splitting constant gamma < 0.05.
9B1 = 2.445, B2 = 1.947 Carlone and Dalby, 1969.
10D1 = 4.48E-4 Carlone and Dalby, 1969, D2 = 18.9E-4; H0 = -12E-7, H1 = -16E-7 Carlone and Dalby, 1969.
11Franck-Condon factors Felenbok, 1963.
12Te has been corrected for the effects of Y00 on the zero-point energy in both upper and lower state and for a small electronic term ovSigma due to interaction with the 2Pi state; see Coxon, 1975.
13The constants represent only v=0...3, Coxon, 1975; Vibrational energy levels and DeltaG values up to v=13 are listed in Carlone and Dalby, 1969. Preliminary vibrational constants may be found in Barrow, 1956.
14Spin splitting constants Coxon, 1975: gamma0 = +0.1201 [good agreement with Douglas, 1974], gamma1 = +0.1170, gamma2 = +0.1114.
15In low-pressure flames and discharges the intensity of emission lines originating in v' = 0, 1, 2 decreases rapidly above N' = 29, 26, 17, respectively Broida and Kane, 1953, owing to predissociation by 4Sigma- (see 15 of O1H); substantially higher N' values in Palmer and Naegeli, 1968 correspond to the first lines of zero intensity. The lifetime of the v' = 0 rotational levels drops sharply above N' ~ 34 Elmergreen and Smith, 1972, Wilcox, Anderson, et al., 1975. A much stronger predissociation occurs for v = 7...12 causing diffuseness in the BrarrowA bands in low pressure discharges Carlone and Dalby, 1969, Czarny, Felenbok, et al., 1971; asymmetric line shapes in the 0-9 band have been studied by Carlone, 1974 and have been found Carlone, 1975 to contain a Q component because of mixing with the 4Pi state that causes the predissociation Czarny, Felenbok, et al., 1971.
16muel(v=0) = 2.16 D Scarl and Dalby, 1971, see note q of O1H. A considerably lower value of 1.72 D was derived by Weinstock and Zare, 1973 from Stark shifts in the location of high-field level crossings and appears to be favored by ab initio calculations [for references see Weinstock and Zare, 1973]. Hfs constants from high-field level crossing experiments in Weinstock and Zare, 1973 [eqQ corrected by Woods and Dixon, 1976 and German, 1976].
17RKR potential functions Coxon, 1975.
18The equilibrium constants refer to the true mechanical Bv values derived by Coxon, 1975 from the effective constants (given in the same paper) for vleq3. Term values for vleq3 Clyne, Coxon, et al., 1973.
19+1.65E-8J3(J+1)3 - 6.0E-13J4(J+1)4 Coxon, 1975; good agreement with D0 and H0 of Douglas, 1974. Coxon, 1975 gives Dv, Hv for vleq2.
20Radiative lifetimes tau(v=0,N=1) = 691 ± 9 ns, tau(v=1,N=1) = 712 ± 10 ns, tau(v=2,N=1) = 736 ± 13 ns German, 1975. Elmergreen and Smith, 1972, Becker and Haaks, 1973, Brophy, Silver, et al., 1974, Wilcox, Anderson, et al., 1975 give somewhat longer lifetimes for low rotational levels in v=0; Hanle effect measurements de Zafra, Marshall, et al., 1971, German, Bergeman, et al., 1973 are slightly lower. Oscillator strengths from high-resolution line absorption: f00 = 0.00096 and f10 = 0.00026 for the rotationless molecule Rouse and Engleman, 1973.
21Zeeman effect in the 0-0 band Thakur, Rai, et al., 1968, Nanes and Robinson, 1971, magnetic rotation spectrum Nanes and Robinson, 1971. Absorption and emission in solid Ne Tinti, 1968. Franck-Condon factors Felenbok, 1963, Coxon, 1975. Vibrational intensity distribution, variation of the transition moment with r, rotational dependence of transition probabilities Crosley and Lengel, 1977.
22A0 = -139.230, A1 = -139.440, A2 = -139.644 Coxon, 1975. Ab initio calculation of spin-orbit coupling parameters Coxon and Hammersley, 1975.
23Lambda-type doubling parameters p0 = +0.1266, q0 = -0.010934; additional constants for vleq3 Coxon, 1975; ab initio calculation Coxon and Hammersley, 1975.
24Term values for vleq3 Clyne, Coxon, et al., 1973.
25D1 = 5.331E-4, D2 = 5.28E-4; H0 = 1.935E-8, H1 = +2.065E-8, H2 = +2.46E-8; L0 = -5.2E-13 Coxon, 1975. For v=0 good agreement with Douglas, 1974.
26Hf Lambda-doubling sp. 30
27Spectrum of 17OD; magnetic hf and electric quadrupole coupling constants.
28From D00(OH) assuming zero electronic isotope shift.
29From I.P.(OH) and the zero-point energies of OH, OD, OH+, OD+. Photoelectron spectroscopy gives 13.01 eV Katsumata and Lloyd, 1977.
30Lambda-doubling and hfs coupling constants. Dipole moment muel(v=0)= 1.65312 D, from Stark shifts of hf Lambda-doubling transitions Meerts and Dymanus, 1973, 2; see also Scarl and Dalby, 1971.


Go To: Top, Gas 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]

Felenbok, 1963
Felenbok, P., Contribution a l'etude du spectre moleculaire des radicaux OH et OD, Ann. Astrophys., 1963, 26, 393. [all data]

Douglas, 1974
Douglas, A.E., Absorption of OH in the 1200 Å region, Can. J. Phys., 1974, 52, 318. [all data]

Barrow, 1956
Barrow, R.F., The B2«SIGMA»+-A2«SIGMA»+ band-systems of OH and OD, Ark. Fys., 1956, 11, 281. [all data]

Herman, Felenbok, et al., 1961
Herman, L.; Felenbok, P.; Herman, R., Spectre d'emission des radicaux OH et OD, J. Phys. Radium, 1961, 22, 83. [all data]

Czarny and Felenbok, 1968
Czarny, J.; Felenbok, P., Etude a tres haute resolution de la transition B2«SIGMA»+ --> A2«SIGMA»+ de OH et OD a l'aide d'une source haute frequence mise au point a cet effet, Ann. Astrophys., 1968, 31, 141. [all data]

Clyne, Coxon, et al., 1973
Clyne, M.A.A.; Coxon, J.A.; Woon Fat, A.R., The A2«SIGMA»+-X2«PI»i electronic band system of the OD free radical. Spectroscopic data for the 0-0 sequence, and rotational term values for A2«SIGMA»+ and X2«PI»i, J. Mol. Spectrosc., 1973, 46, 146. [all data]

Coxon, 1975
Coxon, J.A., The A2«SIGMA»+-X2«PI»i system of OD. Determination of molecular constants by the direct two-state fit approach, J. Mol. Spectrosc., 1975, 58, 1. [all data]

Dousmanis, Sanders, et al., 1955
Dousmanis, G.C.; Sanders, T.M., Jr.; Townes, C.H., Microwave spectra of the free radicals OH and OD, Phys. Rev., 1955, 100, 1735. [all data]

Meerts and Dymanus, 1973
Meerts, W.L.; Dymanus, A., Accurate frequencies below 5 GHz of the lower J states of OD, Astrophys. J., 1973, 180, 93. [all data]

Meerts and Dymanus, 1975
Meerts, W.L.; Dymanus, A., A molecular beam electric resonance study of the hyperfine «LAMBDA» doubling spectrum of OH, OD, SH, and SD, Can. J. Phys., 1975, 53, 2123. [all data]

Carrington and Lucas, 1970
Carrington, A.; Lucas, J.D., Electron resonance of gaseous diatomic hydrides. I. 17O hyperfine and quadrupole interactions in OH and OD, Proc. R. Soc. London A, 1970, 314, 567. [all data]

Smith and Stella, 1975
Smith, Wm.H.; Stella, G., Lifetimes for OH and OD electronic states with resonance transitions in the region between 1700 and 1950 Å, J. Chem. Phys., 1975, 63, 2395. [all data]

Carlone and Dalby, 1969
Carlone, C.; Dalby, F.W., Spectrum of the hydroxyl radical, Can. J. Phys., 1969, 47, 1945. [all data]

Broida and Kane, 1953
Broida, H.P.; Kane, W.R., Rotational intensity distributions of OH and OD in an electrodeless discharge through water vapor, Phys. Rev., 1953, 89, 1053. [all data]

Palmer and Naegeli, 1968
Palmer, H.B.; Naegeli, D.W., Predissociation of chemiluminescent OH and OD, J. Mol. Spectrosc., 1968, 28, 417-421. [all data]

Elmergreen and Smith, 1972
Elmergreen, B.G.; Smith, W.H., Direct measurement of the lifetimes and predissociation probabilities for rotational levels of the OH and OD A2«SIGMA»+ states, Astrophys. J., 1972, 178, 557. [all data]

Wilcox, Anderson, et al., 1975
Wilcox, D.; Anderson, R.; Peacher, J., Rotational and predissociation lifetimes of the A2«SIGMA»+ state of OD, J. Opt. Soc. Am., 1975, 65, 1368. [all data]

Czarny, Felenbok, et al., 1971
Czarny, J.; Felenbok, P.; Lefebvre-Brion, H., High vibrational level predissociation in the A2«SIGMA»+ state of OD, J. Phys. B:, 1971, 4, 124. [all data]

Carlone, 1974
Carlone, C., Asymmetric line shapes in the B --> A system of OD, Phys. Rev. A: Gen. Phys., 1974, 9, 606. [all data]

Carlone, 1975
Carlone, C., Interference effects in the excitation of resonances with fine structure - an application to the predissociation in the B --> A system of the deutroxyl radical, Phys. Rev. A: Gen. Phys., 1975, 12, 2464. [all data]

Scarl and Dalby, 1971
Scarl, E.A.; Dalby, F.W., High-field Stark effects on the near ultraviolet spectrum of the hydroxyl radical, Can. J. Phys., 1971, 49, 2825. [all data]

Weinstock and Zare, 1973
Weinstock, E.M.; Zare, R.N., High-field level-crossing and Stark studies of the A2«SIGMA»+ state of OD, J. Chem. Phys., 1973, 58, 4319. [all data]

Woods and Dixon, 1976
Woods, R.C.; Dixon, T.A., Comment on the quadrupole coupling constants in the A2«SIGMA»+ states of OD and NO, J. Chem. Phys., 1976, 64, 5319. [all data]

German, 1976
German, K.R., High field level crossing measurements of tha A2«SIGMA»+ state of OD, J. Chem. Phys., 1976, 64, 4192. [all data]

German, 1975
German, K.R., Direct measurement of the radiative lifetimes of the A2«SIGMA»+ (V' = 0) states of OH and OD, J. Chem. Phys., 1975, 62, 2584. [all data]

Becker and Haaks, 1973
Becker, K.H.; Haaks, D., Measurement of the natural lifetimes and quenching rate constants of OH(2«SIGMA»+, v = 0,1) and OD(2«SIGMA»+, v = 0,1) radicals, Z. Naturforsch. A, 1973, 28, 249. [all data]

Brophy, Silver, et al., 1974
Brophy, J.H.; Silver, J.A.; Kinsey, J.L., Direct measurement of the radiative lifetime of the A2«SIGMA»+(v' = 0, K' = 1, J' = 3/2) state of OH and OD, Chem. Phys. Lett., 1974, 28, 418. [all data]

de Zafra, Marshall, et al., 1971
de Zafra, R.L.; Marshall, A.; Metcalf, H., Measurement of lifetime and g factors by level crossing and optical double resonance in the OH and OD free radicals, Phys. Rev. A: Gen. Phys., 1971, 3, 1557. [all data]

German, Bergeman, et al., 1973
German, K.R.; Bergeman, T.H.; Weinstock, E.M.; Zare, R.N., Zero-field level crossing and optical radio-frequency double resonance studies of the A2«SIGMA»+ states of OH and OD, J. Chem. Phys., 1973, 58, 4304. [all data]

Rouse and Engleman, 1973
Rouse, P.E.; Engleman, R., Jr., Oscillator strengths from line absorption in a high-temperature furnace. I. The (0,0) and (1,0) bands of the A2«SIGMA»+-X2«PI»i transition in OH and OD, J. Quant. Spectrosc. Radiat. Transfer, 1973, 13, 1503. [all data]

Thakur, Rai, et al., 1968
Thakur, S.N.; Rai, D.K.; Singh, N.L., Zeeman effect in the (0, 0) band of OD, J. Chem. Phys., 1968, 48, 3389. [all data]

Nanes and Robinson, 1971
Nanes, R.; Robinson, D.W., Magnetic rotation spectra of the A2«SIGMA»+-X2«PI»i transition of OH and OD, J. Chem. Phys., 1971, 55, 963. [all data]

Tinti, 1968
Tinti, D.S., Absorption and emission spectra of OH and OD in solid Ne. Evidence for rotation, J. Chem. Phys., 1968, 48, 1459. [all data]

Crosley and Lengel, 1977
Crosley, D.R.; Lengel, R.K., Relative transition probabilities in the A-X system of OD, J. Quant. Spectrosc. Radiat. Transfer, 1977, 17, 59. [all data]

Coxon and Hammersley, 1975
Coxon, J.A.; Hammersley, R.E., Spin-orbit coupling and «LAMBDA»-type doubling in the ground state of OD, X2«PI». Comparison of experimental constants with ab initio calculations, J. Mol. Spectrosc., 1975, 58, 29. [all data]

Katsumata and Lloyd, 1977
Katsumata, S.; Lloyd, D.R., The photoelectron spectra of the OH and OD radicals, Chem. Phys. Lett., 1977, 45, 519. [all data]

Meerts and Dymanus, 1973, 2
Meerts, W.L.; Dymanus, A., Electric dipole moments of OH and OD by molecular beam electric resonance, Chem. Phys. Lett., 1973, 23, 45. [all data]


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