iron oxide
- Formula: FeO
- Molecular weight: 71.844
- IUPAC Standard InChI: InChI=1S/Fe.O
- IUPAC Standard InChIKey: UQSXHKLRYXJYBZ-UHFFFAOYSA-N
- CAS Registry Number: 1345-25-1
- 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: Iron monoxide
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, 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 |
|---|---|---|---|---|---|
| ΔfH°gas | 60.000 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1965 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°gas,1 bar | 57.820 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1965 |
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.
View plot Requires a JavaScript / HTML 5 canvas capable browser.
| Temperature (K) | 5000. to 6000. |
|---|---|
| A | 8.650710 |
| B | -0.024152 |
| C | 0.154889 |
| D | -0.016799 |
| E | 0.056932 |
| F | 57.23490 |
| G | 67.76360 |
| H | 60.00010 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in June, 1965 |
Condensed phase thermochemistry data
Go To: Top, Gas phase thermochemistry data, 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 |
|---|---|---|---|---|---|
| ΔfH°liquid | -59.639 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1965 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°liquid,1 bar | 18.02 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1965 |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔfH°solid | -65.019 | kcal/mol | Review | Chase, 1998 | Data last reviewed in June, 1965 |
| Quantity | Value | Units | Method | Reference | Comment |
| S°solid | 14.52 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in June, 1965 |
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.
View plot Requires a JavaScript / HTML 5 canvas capable browser.
| Temperature (K) | 1650. to 5000. |
|---|---|
| A | 16.30000 |
| B | -1.075821×10-10 |
| C | 2.856662×10-11 |
| D | -2.543741×10-12 |
| E | -7.391681×10-11 |
| F | -67.26401 |
| G | 32.94400 |
| H | -59.63960 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in June, 1965 |
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 1650. |
|---|---|
| A | 10.93480 |
| B | 4.489850 |
| C | -1.422610 |
| D | 0.203819 |
| E | -0.019423 |
| F | -68.53320 |
| G | 26.36520 |
| H | -65.02010 |
| Reference | Chase, 1998 |
| Comment | Data last reviewed in June, 1965 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, 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.
Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
B - John E. Bartmess
View reactions leading to FeO+ (ion structure unspecified)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| Proton affinity (review) | 217. | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
| Quantity | Value | Units | Method | Reference | Comment |
| Gas basicity | 210.4 | kcal/mol | N/A | Hunter and Lias, 1998 | HL |
Electron affinity determinations
| EA (eV) | Method | Reference | Comment |
|---|---|---|---|
| 1.49450 ± 0.00022 | ZEKE | Drechsler, Boesl, et al., 1997 | B |
| 1.492 ± 0.020 | LPES | Engelking and Lineberger, 1977 | B |
| 1.500 ± 0.040 | LPES | Wu, Desai, et al., 1996 | B |
| 1.49303 | LPES | Anderson, Lykke, et al., 1987 | B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 8.9 ± 0.16 | END | Armentrout, Halle, et al., 1982 | LBLHLM |
| 8.71 ± 0.10 | EI | Hildenbrand, 1975 | LLK |
| 8. ± 1. | EI | Balducci, DeMaria, et al., 1971 | LLK |
Constants of diatomic molecules
Go To: Top, Gas phase thermochemistry data, Condensed 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 June, 1977
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| R | 41480 H | |||||||||||
| ↳missing citation; Bass, Kuebler, et al., 1964; missing citation | ||||||||||||
| c | 26441 | [545] H | c → A 1 R | 22326 H | ||||||||
| ↳Rosen, 1945; Malet and Rosen, 1945; West and Broida, 1975 | ||||||||||||
| c' | 23569 | [535] H 2 | c' → A 1 R | 19449 H | ||||||||
| ↳West and Broida, 1975 | ||||||||||||
| b | 21962 | [667] H | [0.4717] 3 | [1.695] | b 4 ↔ A 1 R | 17908 H | ||||||
| ↳Rosen, 1945; missing citation; missing citation; Callear and Norrish, 1960; Bass, Kuebler, et al., 1964; Barrow and Senior, 1969; West and Broida, 1975 | ||||||||||||
| (21865) | [(661)] H | b 4 ↔ A 4 1 R | 17808 H | |||||||||
| ↳Rosen, 1945; missing citation; missing citation; Callear and Norrish, 1960; Bass, Kuebler, et al., 1964; Barrow and Senior, 1969; West and Broida, 1975 | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| a | 21245 | 820 H | 1 | [0.497] 5 | [1.651] | a 6 ↔ A 1 R | 17267 H | |||||
| ↳Rosen, 1945; missing citation; missing citation; Callear and Norrish, 1960; Bass, Kuebler, et al., 1964; West and Broida, 1975 | ||||||||||||
| B (5Π) | 14404 | 650 7 H | 5 8 | B → A 1 R | 10340 H | |||||||
| ↳Bass and Benedict, 1952; West and Broida, 1975 | ||||||||||||
| B → X R | 14245 H | |||||||||||
| ↳Malet and Rosen, 1945; Bass and Benedict, 1952; West and Broida, 1975 | ||||||||||||
| A 5Σ+ | 3948 9 | 880.53 3 Z | 4.63 | 0.51271 3 | 0.00376 | [6.6E-7] | 1.6259 | 3905 10 | ||||
| ↳Malet and Rosen, 1945; West and Broida, 1975; Engelking and Lineberger, 1977 | ||||||||||||
| State | Te | ωe | ωexe | ωeye | Be | αe | γe | De | βe | re | Trans. | ν00 |
| X 5Δ | 0 9 | 965 7 | (1.57) 11 | 12 | ||||||||
Notes
| 1 | The similarity of the vibrational constants suggests a common lower state for the five systems. Uncertain. |
| 2 | Fragments of an emission system, 18500 - 20000 cm-1. |
| 3 | From the rotational analysis Barrow and Senior, 1969 of four bands of the short-wavelength component of b-A. They appear to be the Ω'= Ω" = 0 subbands of a quintet or septet Σ-Σ transition. An earlier analysis by Dhumwad and Narasimham, 1967 is incorrect. |
| 4 | Lifetime τ ~ 500 ns West and Broida, 1975. |
| 5 | Rotational analysis using tunable-laser excited fluorescence spectroscopy West and Broida, 1975. |
| 6 | Lifetime τ ~ 450 ns West and Broida, 1975. |
| 7 | From a re-analysis of B → X by Engelking and Lineberger, 1977. The FeO- photoelectron spectrum Engelking and Lineberger, 1977 gives a ground state frequency of 970 ± 60 cm-1 |
| 8 | Large number of emission bands, 7100 - 15000 cm-1; tentative vibrational analysis. |
| 9 | Symmetries assigned Engelking and Lineberger, 1977 on the basis of ab initio calculations Bagus and Preston, 1973. |
| 10 | From 0-0 band assignments for B → X Engelking and Lineberger, 1977 and B → A Bass and Benedict, 1952, West and Broida, 1975. From the FeO- photoelectron spectrum Engelking and Lineberger, 1977 obtain 3990 ± 100 cm-1. |
| 11 | Estimated Engelking and Lineberger, 1977 from relative vibrational intensities in the photoelectron spectrum of FeO-. |
| 12 | The IR transition strength measured at 880 cm-1 von Rosenberg and Wray, 1972, Fissan and Sulzmann, 1972 requires reinterpretation in view of the recent reassignment of the low-lying states Engelking and Lineberger, 1977. |
| 13 | Thermochemica1 value (mass-spectrom.) Cheetam and Barrow, 1967, Balducci, DeMaria, et al., 1971, Hildenbrand, 1975. See also Brewer and Mastick, 1951, Lagerqvist and Huldt, 1953. |
| 14 | Electron impact appearance potential Hildenbrand, 1975. |
| 15 | From D00(FeO) and the electron affinities of FeO and O. |
| 16 | From the laser photoelectron spectrum of FeO- Engelking and Lineberger, 1977. |
References
Go To: Top, Gas phase thermochemistry data, Condensed 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]
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]
Drechsler, Boesl, et al., 1997
Drechsler, G.; Boesl, U.; Bassmann, C.; Schlag, E.W.,
Mass selected anion-zero kinetic energy photoelectron spectroscopy (anion-ZEKE): Ground and low excited states of FeO,
J. Chem. Phys., 1997, 107, 7, 2284-2291, https://doi.org/10.1063/1.474622
. [all data]
Engelking and Lineberger, 1977
Engelking, P.C.; Lineberger, W.C.,
Laser photoelecton spectrometry of FeO-: Electron affinity, electronic state separations, and ground state vibrations of iron oxide, and a new ground state assignment,
J. Chem. Phys., 1977, 66, 5054. [all data]
Wu, Desai, et al., 1996
Wu, H.; Desai, R.; Wang, L.-S.,
Observation and Photoelectron Spectroscopic Study of Novel Mono- and Di-iron Oxide Molecules: FeOy- (y=1-4) and Fe2Oy- (y=1-5),
J. Am. Chem. Soc., 1996, 118, 22, 5296, https://doi.org/10.1021/ja954153b
. [all data]
Anderson, Lykke, et al., 1987
Anderson, T.; Lykke, K.R.; Neumark, D.M.; Lineberger, W.C.,
Autodetachment Study of the Electronic Spectroscopy of FeO-,
J. Chem. Phys., 1987, 86, 4, 1858, https://doi.org/10.1063/1.452137
. [all data]
Armentrout, Halle, et al., 1982
Armentrout, P.B.; Halle, L.F.; Beauchamp, J.L.,
Reaction of Cr+, Mn+, Fe+, Co+, and Ni+ with O2 and N2O. Examination of the translational energy dependence of the cross sections of endothermic reactions,
J. Chem. Phys., 1982, 76, 2449. [all data]
Hildenbrand, 1975
Hildenbrand, D.L.,
Thermochemistry of molecular FeO, FeO+ and FeO2,
Chem. Phys. Lett., 1975, 34, 352. [all data]
Balducci, DeMaria, et al., 1971
Balducci, G.; DeMaria, G.; Guido, M.; Piacente, V.,
Dissociation energy of FeO,
J. Chem. Phys., 1971, 55, 2596. [all data]
Bass, Kuebler, et al., 1964
Bass, A.M.; Kuebler, N.A.; Nelson, L.S.,
Observation of FeO in absorption by flash heating and kinetic spectroscopy,
J. Chem. Phys., 1964, 40, 3121. [all data]
Rosen, 1945
Rosen, B.,
Spectra of diatomic oxides by the method of exploded wire,
Nature (London), 1945, 156, 570. [all data]
Malet and Rosen, 1945
Malet, L.; Rosen, B.,
Contribution a l'etude du spectre de FeO,
Bull. Soc. R. Sci. Liege, 1945, 14, 377. [all data]
West and Broida, 1975
West, J.B.; Broida, H.P.,
Chemiluminescence and photoluminescence of diatomic iron oxide,
J. Chem. Phys., 1975, 62, 2566. [all data]
Callear and Norrish, 1960
Callear, A.B.; Norrish, R.G.W.,
The behaviour of additives in explosions and the mechanism of antiknock,
Proc. R. Soc. London A, 1960, 259, 304-324. [all data]
Barrow and Senior, 1969
Barrow, R.F.; Senior, M.,
Ground state of gaeous FeO,
Nature (London), 1969, 223, 1359. [all data]
Bass and Benedict, 1952
Bass, A.M.; Benedict, W.S.,
A new infrared band system of FeO,
Astrophys. J., 1952, 116, 652. [all data]
Dhumwad and Narasimham, 1967
Dhumwad, R.K.; Narasimham, N.A.,
Rotational analysis of some of the bands of the orange system of FeO,
Proc. Indian Acad. Sci. Sect. A, 1967, 64, 283. [all data]
Bagus and Preston, 1973
Bagus, P.S.; Preston, H.J.T.,
Lowest 5Σ+ state of FeO: an ab initio investigation,
J. Chem. Phys., 1973, 59, 2986. [all data]
von Rosenberg and Wray, 1972
von Rosenberg, C.W., Jr.; Wray, K.L.,
Shock tube studies on Fe(CO)5+O2: 11μ FeO emission and kinetics,
J. Quant. Spectrosc. Radiat. Transfer, 1972, 12, 531. [all data]
Fissan and Sulzmann, 1972
Fissan, H.; Sulzmann, K.G.P.,
Absorption coefficients for the infrared vibration-rotation spectrum of FeO,
J. Quant. Spectrosc. Radiat. Transfer, 1972, 12, 979. [all data]
Cheetam and Barrow, 1967
Cheetam, C.J.; Barrow, R.F.,
Adv. High Temp. Chem., 1967, 1, 7. [all data]
Brewer and Mastick, 1951
Brewer, L.; Mastick, D.F.,
The stability of gaseous diatomic oxides,
J. Chem. Phys., 1951, 19, 834. [all data]
Lagerqvist and Huldt, 1953
Lagerqvist, A.; Huldt, L.,
Die Dissoziationsenergien der gasformigen Oxyde CrO und FeO,
Z. Naturforsch. A, 1953, 8, 493. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Constants of diatomic molecules, References
- Symbols used in this document:
EA Electron affinity 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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