niobium oxide


Gas phase thermochemistry data

Go To: Top, Gas phase ion energetics 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
Δfgas198.74kJ/molReviewChase, 1998Data last reviewed in December, 1973
Quantity Value Units Method Reference Comment
gas,1 bar238.87J/mol*KReviewChase, 1998Data last reviewed in December, 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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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

View table.

Temperature (K) 3000. to 6000.
A 35.73230
B 0.800852
C 0.023404
D 0.018463
E -0.511085
F 186.3110
G 278.9980
H 198.7400
ReferenceChase, 1998
Comment Data last reviewed in December, 1973

Gas phase ion energetics 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.

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

Ionization energy determinations

IE (eV) Method Reference Comment
7.91 ± 0.02PEDyke, Ellis, et al., 1987LBLHLM
7.0 ± 0.5EIBalducci, Gigli, et al., 1987LBLHLM

Constants of diatomic molecules

Go To: Top, Gas phase thermochemistry data, 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 October, 1975

Symbols used in the table of constants
SymbolMeaning
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 93Nb16O
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
G 4Σ- 1 21385.3 850.5 Z 3.37  0.4001 1 0.0019  2.7E-7  1.7572 G ↔ X R 21316.2 Z
Rao, 1950; missing citation; missing citation; missing citation; Singh and Shukla, 1972; Brom, Durham, et al., 1974
F (20740) (908) 2 (4)        F ← X 2 (20704)
Brom, Durham, et al., 1974
D (16640) [(932)] 3         D ← X 3 (16618)
Brom, Durham, et al., 1974
C (15580) (904) 3 (2)        C ← X 3 (15544)
Green, Korfmacher, et al., 1973; Brom, Durham, et al., 1974
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
B (15300) (891) 3 (4)        B ← X 3 (15256)
Brom, Durham, et al., 1974
E (15270) (847) 3         E ← X 3 (15206)
Brom, Durham, et al., 1974
A'           A' ← X 3 (14467)
Brom, Durham, et al., 1974
(13720) [(899)] 3         A ← X 3 (13676)
Brom, Durham, et al., 1974
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
X 4Σ- 0 1 989.0 Z 3.83  0.4321 1 0.0021  2.2E-7  1.6909 4  
Green, Korfmacher, et al., 1973; Brom, Durham, et al., 1974

Notes

1The rotational analysis by Uhler, 1954 of seven bands in the G-X system assumed that they represent a 2Δ-2Δ transition. More recently, additional branches were found Richards, 1969, Dunn, 1972 having very wide nuclear hyperfine structure [b ~0.19 cm-1 Femenias, Athenour, et al., 1974, as compared to b ~0.165 cm-1 Brom, Durham, et al., 1974 from the matrix ESR spectrum Brom, Durham, et al., 1974]. The four branches of Uhler, 1954 probably represent the F2 and F3 components of the 4Σ- - 4Σ- transition. The rotational analysis by Rao, 1954 appears to be in error.
2Only observed in a Ne matrix where the F state interacts with the nearby G 4Σ- state.
3Absorption in rare gas matrices. Data are for Ne except for E←X which is only observed in Ar. So far, no satisfactory analysis was given for the complex systems of R shaded emission bands in the gas phase spectrum from 13300 to 18200 cm-1 Rao, 1950, Rao and Premaswarup, 1953, Gatterer, Junkes, et al., 1957*; see, however, Dunn, 1972, Femenias, Athenour, et al., 1974.
4IR and ESR sp. 6
5Thermochemical value (mass-spectrometry Shchukarev, Semenov, et al., 1966).
6In rare gas matrices.

References

Go To: Top, Gas phase thermochemistry data, 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.

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

Dyke, Ellis, et al., 1987
Dyke, J.M.; Ellis, A.M.; Feher, M.; Morris, A.; Paul, A.J.; Stevens, J.C.H., High-temperature photoelectron spectroscopy - A study of niobium monoxide and tantalum monoxide, J. Chem. Soc. Faraday Trans. 2, 1987, 83, 1555. [all data]

Balducci, Gigli, et al., 1987
Balducci, G.; Gigli, G.; Guido, M., Thermochemical study of the gaseous molecules EuNbO3, EuNbO2, EuNb2O6 and of the niobium oxides NbO and NbO2, Ber. Bunsen-Ges. Phys. Chem., 1987, 91, 635. [all data]

Rao, 1950
Rao, V.R., The complex band spectrum of columbium oxide (the diatomic molecule CbO), Indian J. Phys., 1950, 24, 35. [all data]

Singh and Shukla, 1972
Singh, P.D.; Shukla, M.M., Vibrational transition probabilities and r-centroids for some diatomic molecular band systems, J. Quant. Spectrosc. Radiat. Transfer, 1972, 12, 1249. [all data]

Brom, Durham, et al., 1974
Brom, J.M., Jr.; Durham, C.H., Jr.; Weltner, W., Jr., NbO molecule: ESR and optical spectra in enert matrices at 4°K; establishment of its ground electronic state as 4Σ, J. Chem. Phys., 1974, 61, 970. [all data]

Green, Korfmacher, et al., 1973
Green, D.W.; Korfmacher, W.; Gruen, D.M., Infrared absorption spectra of isotopic NbN and NbO isolated in an Ar matrix, J. Chem. Phys., 1973, 58, 404. [all data]

Uhler, 1954
Uhler, U., The blue band-system of niobium oxide, Ark. Fys., 1954, 8, 265. [all data]

Richards, 1969
Richards, D., Thesis, Oxford, 1969, 1. [all data]

Dunn, 1972
Dunn, T.M., Nuclear Hyperfine Structure in the Electronic Spectra of Diatomic Molecules in Molecular Spectroscopy: Modern Research, K.N. Rao and C.W. Mathews, ed(s)., Academic Press, 1972, 231-257. [all data]

Femenias, Athenour, et al., 1974
Femenias, J.L.; Athenour, C.; Stringat, R., Theoretical calculations of relative intensities in hyperfine diatomic transitions, Can. J. Phys., 1974, 52, 361. [all data]

Rao, 1954
Rao, K.S., Rotational analysis of the columbium oxide bands, Nature (London), 1954, 173, 1240. [all data]

Rao and Premaswarup, 1953
Rao, V.R.; Premaswarup, D., The complex band spectrum of the diatomic molecule CbO in the photographic infrared, Indian J. Phys., 1953, 27, 399. [all data]

Gatterer, Junkes, et al., 1957
Gatterer, A.; Junkes, J.; Salpeter, E.W., Molecular spectra of metallic oxides, Specola Vaticana, Citta del Vaticano, 1957, 0. [all data]

Shchukarev, Semenov, et al., 1966
Shchukarev, S.A.; Semenov, G.A.; Frantseva, K.E., A thermodynamic study of the volatilisation of lower oxides of niobium, Russ. J. Inorg. Chem. Engl. Transl., 1966, 11, 129, In original 233. [all data]


Notes

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