Iodine oxide
- Formula: IO
- Molecular weight: 142.9039
- IUPAC Standard InChI: InChI=1S/IO/c1-2
- IUPAC Standard InChIKey: AFSVSXMRDKPOEW-UHFFFAOYSA-N
- CAS Registry Number: 14696-98-1
- Chemical structure:
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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 compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
B - John E. Bartmess
Electron affinity determinations
| EA (eV) | Method | Reference | Comment |
|---|---|---|---|
| 2.3780 ± 0.0050 | LPES | Gilles, Polak, et al., 1991 | B |
| 2.09 ± 0.22 | R-A | Refaey and Franklin, 1976 | I- + O2 ->.; B |
| >1.95355 | R-A | Vogt and Mischke, 1977 | I- + CO ->.; B |
| >1.70 ± 0.36 | R-A | Vogt, Dreves, et al., 1977 | I- + O2 ->.; B |
| 1.76492 | R-A | Refaey and Franklin, 1976, 2 | I- + SO2 ->.; B |
| >-0.503024 | R-A | Henglein and Muccini, 1959 | O- + I2 ->. Revised per new thermo values.; B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 9.66 ± 0.10 | DER | Monks, Stief, et al., 1995 | LL |
| 9.66 ± 0.10 | DER | Monks, Stief, et al., 1995 | LL |
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 January, 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A 2Π3/2 | 21557.81 | 514.57 1 | 5.52 | 0.27635 2 | 0.00273 | 3.2E-7 | 2.0723 | A ↔ X1 3 R | 21474.05 Z | |||
| ↳missing citation; missing citation; missing citation | ||||||||||||
| X2 2Π1/2 | (2330) 4 | |||||||||||
| X1 2Π3/2 | 0 | 681.47 Z | 4.29 5 | 0.34026 6 | 0.002696 7 | 3.6E-7 | 1.8676 8 | |||||
| ↳Saito, 1973 | ||||||||||||
| EPR sp. | ||||||||||||
| ↳Carrington, Dyer, et al., 1970; Brown, Byfleet, et al., 1972 | ||||||||||||
Notes
| 1 | missing note |
| 2 | The rotational lines of absorption bands with v'=0 and 2 are sharp; the lines of the 3-0 absorption band are distinctly diffuse, and the 1-0 and 4-0 bands are completely diffuse owing to predissociation Durie and Ramsay, 1958. |
| 3 | Franck-Condon factors Rao, Rao, et al., 1974. |
| 4 | Estimated by Brown, Byfleet, et al., 1972, from spin-orbit coupling of component atoms. |
| 5 | missing note |
| 6 | From the microwave spectrum Saito, 1973 obtained B0(2Π3/2) = 0.338804 which agrees well with the value from the electronic spectrum. |
| 7 | missing note |
| 8 | Microwave sp. 10 |
| 9 | Based on an extrapolation of the vibrational levels of A 2Π3/2 and on the assumption that A dissociates into 2P3/2 + 1D. Flame photometry Phillips and Sugden, 1961 gives a value of 2.4 eV which seems less likely since it is as high as the value for BrO. The observed predissociation in A indicates D00 ≤ 2.72 eV. Extrapolation of the ground state gives D00= 1.94 eV Trivedi and Gohel, 1972. |
| 10 | Magnetic hyperfine interaction, nuclear quadrupole coupling and constant. |
References
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.
Gilles, Polak, et al., 1991
Gilles, M.K.; Polak, M.L.; Lineberger, W.C.,
Photoelectron Spectroscopy of IO-,
J. Chem. Phys., 1991, 95, 6, 4723, https://doi.org/10.1063/1.461746
. [all data]
Refaey and Franklin, 1976
Refaey, K.M.A.; Franklin, J.L.,
Endoergic ion-molecule-collision processes of negative ions. III. Collisions of I- on O2, CO and CO2,
Int. J. Mass Spectrom. Ion Phys., 1976, 20, 19. [all data]
Vogt and Mischke, 1977
Vogt, D.; Mischke, J.,
Endoergic Ion-Molecule Collision Processes of Negative Ions in Collisions of I- on CO,
Phys. Lett., 1977, 60A, 1, 19, https://doi.org/10.1016/0375-9601(77)90305-X
. [all data]
Vogt, Dreves, et al., 1977
Vogt, D.; Dreves, W.; Mischke, J.,
Energy dependence of differential cross sections in endoergic ion-molecule collision processes of negative ions,
Int. J. Mass Spectrom. Ion Phys., 1977, 24, 285. [all data]
Refaey and Franklin, 1976, 2
Refaey, K.M.A.; Franklin, J.L.,
Endoergic ion-molecule-collision processes of negative ions. I. Collision of I- on SO2,
J. Chem. Phys., 1976, 65, 1994. [all data]
Henglein and Muccini, 1959
Henglein, A.; Muccini, G.A.,
Negative Ion-Molecule Reactions,
J. Chem. Phys., 1959, 31, 5, 1426, https://doi.org/10.1063/1.1730618
. [all data]
Monks, Stief, et al., 1995
Monks, P.S.; Stief, L.J.; Tardy, D.C.; Liebman, J.F.; Zhang, Z.; Kuo, S.-C.; Klemm, R.B.,
Discharge flow-photoionization mass spectrometric study of HOI: Photoionization efficiency spectrum and ionization energy,
J. Phys. Chem., 1995, 99, 16566. [all data]
Saito, 1973
Saito, S.,
Microwave spectrum of the IO radical,
J. Mol. Spectrosc., 1973, 48, 530. [all data]
Carrington, Dyer, et al., 1970
Carrington, A.; Dyer, P.N.; Levy, D.H.,
Gas-phase electron resonance spectra of BrO and IO,
J. Chem. Phys., 1970, 52, 309. [all data]
Brown, Byfleet, et al., 1972
Brown, J.M.; Byfleet, C.R.; Howard, B.J.; Russell, D.K.,
The electron resonance spectra of BrO, IO and SeF in J=5/2 rotational levels,
Mol. Phys., 1972, 23, 457. [all data]
Durie and Ramsay, 1958
Durie, R.A.; Ramsay, D.A.,
Absorption spectra of the halogen monoxides,
Can. J. Phys., 1958, 36, 35. [all data]
Rao, Rao, et al., 1974
Rao, M.L.P.; Rao, D.V.K.; Rao, P.T.,
Dissociation energies, r-centroids and Franck-Condon factors of IO molecule,
Phys. Lett. A, 1974, 50, 341. [all data]
Phillips and Sugden, 1961
Phillips, L.F.; Sugden, T.M.,
Determination of dissociation constants and heats of formation of molecules by flame photometry. Part 7. Flame photometric study of the IO radical,
Trans. Faraday Soc., 1961, 57, 914. [all data]
Trivedi and Gohel, 1972
Trivedi, V.M.; Gohel, V.B.,
Dissociation energy of the IO molecule,
J. Phys. B:, 1972, 5, 38. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Constants of diatomic molecules, References
- Symbols used in this document:
EA Electron affinity - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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