niobium oxide
- Formula: NbO
- Molecular weight: 108.9058
- IUPAC Standard InChI: InChI=1S/Nb.O
- IUPAC Standard InChIKey: BFRGSJVXBIWTCF-UHFFFAOYSA-N
- CAS Registry Number: 12034-57-0
- 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. - Other names: Niobium 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 | 47.500 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas,1 bar | 57.091 | cal/mol*K | Review | Chase, 1998 | Data 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 (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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| Temperature (K) | 3000. to 6000. |
|---|---|
| A | 8.540225 |
| B | 0.191408 |
| C | 0.005594 |
| D | 0.004413 |
| E | -0.122152 |
| F | 44.52940 |
| G | 66.68212 |
| H | 47.50000 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in December, 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 | -80.483 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°liquid,1 bar | 19.89 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in December, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔfH°solid | -100.30 | kcal/mol | Review | Chase, 1998 | Data last reviewed in December, 1973 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid | 11.00 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in December, 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) | 2210. to 3000. |
|---|---|
| A | 14.99952 |
| B | 0.000373 |
| C | -0.000108 |
| D | 0.000011 |
| E | 0.000321 |
| F | -88.60086 |
| G | 32.44073 |
| H | -80.48351 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in December, 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.
View plot Requires a JavaScript / HTML 5 canvas capable browser.
| Temperature (K) | 298. to 2210. |
|---|---|
| A | 10.27806 |
| B | 2.114613 |
| C | 0.004440 |
| D | -0.001371 |
| E | -0.096227 |
| F | -103.7813 |
| G | 22.26568 |
| H | -100.3000 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in December, 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 October, 1975
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 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 | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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 | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | 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
| 1 | The 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. |
| 2 | Only observed in a Ne matrix where the F state interacts with the nearby G 4Σ- state. |
| 3 | Absorption 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. |
| 4 | IR and ESR sp. 6 |
| 5 | Thermochemical value (mass-spectrometry Shchukarev, Semenov, et al., 1966). |
| 6 | In rare gas matrices. |
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]
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, 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 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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