Cesium iodide
- Formula: CsI
- Molecular weight: 259.80992
- IUPAC Standard InChI: InChI=1S/Cs.HI/h;1H/q+1;/p-1
- IUPAC Standard InChIKey: XQPRBTXUXXVTKB-UHFFFAOYSA-M
- CAS Registry Number: 7789-17-5
- 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: caesium iodide
- Permanent link for this species. Use this link for bookmarking this species for future reference.
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Phase change data
Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering 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 by: William E. Acree, Jr., James S. Chickos
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔsubH° | 45.67 | kcal/mol | MS | Viswanathan and Hilpert, 2010 | See also Pankajavalli, Mallika, et al., 1998. |
| ΔsubH° | 46.75 | kcal/mol | GS | Pankajavalli, Mallika, et al., 1998 | |
| ΔsubH° | 46.15 | kcal/mol | T | Cordfunke, 1986 | See also Pankajavalli, Mallika, et al., 1998. |
| ΔsubH° | 46.15 | kcal/mol | T | Venugopal, Prasad, et al., 1985 | See also Pankajavalli, Mallika, et al., 1998. |
Reaction thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: John E. Bartmess
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
+
= (
•
)
By formula: I- + CsI = (I- • CsI)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 33.700 ± 0.050 | kcal/mol | N/A | Wang, Wang, et al., 2010 | gas phase |
| ΔrH° | 36.1 ± 1.3 | kcal/mol | N/A | Gusarov, Gorokhov, et al., 1979 | gas phase; value altered from reference due to conversion from electron convention to ion convention |
Gas phase ion energetics data
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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
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
B - John E. Bartmess
Electron affinity determinations
| EA (eV) | Reference | Comment |
|---|---|---|
| 0.630 ± 0.040 | Miller, Leopold, et al., 1986 | Extrapolated by polarizability and radius from experimental data.; B |
Ionization energy determinations
| IE (eV) | Method | Reference | Comment |
|---|---|---|---|
| 7.1 | PE | Benson, Novak, et al., 1987 | LBLHLM |
| 7.2 ± 0.2 | EI | Viswanathan and Hilpert, 1984 | LBLHLM |
| 6.7 ± 0.4 | EI | Emons, Horlbeck, et al., 1982 | LBLHLM |
| 7.1 ± 0.1 | PE | Potts and Price, 1977 | LLK |
| 6.5 ± 0.2 | PE | Smith and Pong, 1975 | LLK |
| 7.1 ± 0.1 | PE | Potts, Williams, et al., 1974 | LLK |
| 7.10 ± 0.05 | PE | Berkowitz, Dehmer, et al., 1973 | LLK |
| 7.25 ± 0.05 | PI | Berkowitz, 1969 | RDSH |
| 7.46 ± 0.05 | PE | Timoshenko and Akopyan, 1974 | Vertical value; LLK |
| 7.2 | PE | Goodman, Allen, et al., 1974 | Vertical value; LLK |
Appearance energy determinations
| Ion | AE (eV) | Other Products | Method | Reference | Comment |
|---|---|---|---|---|---|
| Cs+ | 7.46 ± 0.05 | I | PI | Berkowitz, 1969 | RDSH |
| I+ | 14.1 ± 0.3 | Cs | EI | Platel, 1965 | RDSH |
| Cs+ | 17.60 ± 0.04 | I(-) | PE | Potts and Price, 1977 | Vertical value; LLK |
| Cs+ | 19.31 ± 0.04 | I(-) | PE | Potts and Price, 1977 | Vertical value; LLK |
Ion clustering data
Go To: Top, Phase change data, Reaction 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.
Data compiled by: John E. Bartmess
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
+
= (
•
)
By formula: I- + CsI = (I- • CsI)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 33.700 ± 0.050 | kcal/mol | N/A | Wang, Wang, et al., 2010 | gas phase |
| ΔrH° | 36.1 ± 1.3 | kcal/mol | N/A | Gusarov, Gorokhov, et al., 1979 | gas phase; value altered from reference due to conversion from electron convention to ion convention |
Constants of diatomic molecules
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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 November, 1976
| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Autoionizing levels at and above 12.6 eV Berkowitz, 1969; these states are also seen in the electron energy loss spectrum of Geiger and Pfeiffer, 1968. Interpretation analogous to CsBr. | ||||||||||||
| ↳Geiger and Pfeiffer, 1968; Berkowitz, 1969 | ||||||||||||
| Continuous absorption with maxima at 54050, 50250, 46500, 41400, 38800, 30900 cm-1 Schmidt-Ott, 1931, Barrow and Caunt, 1953, Davidovits and Brodhead, 1967, followed by diffuse absorption bands (fluctuation b.) in the region 29140 - 22900 cm-1 Sommermeyer, 1929, Barrow and Caunt, 1953. The chemiluminescence spectrum Oldenborg, Gole, et al., 1974 consisting of a long lower-state vibrational progression extends from 25000 - 18000 cm-1. See note d of CsBr. | ||||||||||||
| ↳Sommermeyer, 1929; Schmidt-Ott, 1931; Barrow and Caunt, 1953; Davidovits and Brodhead, 1967; Oldenborg, Gole, et al., 1974 | ||||||||||||
| X 1Σ+ | 0 | 119.178 1 | 0.2505 1 | 0.023627357 | 0.000068263 2 | 3.7146E-09 3 | 0.00230 | 3.315192 4 | ||||
| ↳Honig, Stitch, et al., 1953; Rusk and Gordy, 1962; Honerjager and Tischer, 1974 | ||||||||||||
Notes
| 1 | Derived from the rotational constants Honerjager and Tischer, 1974. See also Barrow and Caunt, 1953, Rice and Klemperer, 1957. |
| 2 | αv= +4.89E-8(v+1/2)2 + 1.14E-10(v+1/2)3 Honerjager and Tischer, 1974. |
| 3 | Also higher order constants Honerjager and Tischer, 1974. |
| 4 | Microwave sp. 7 |
| 5 | Average of a thermochemical value Brewer and Brackett, 1961 and a value obtained from photodissociative ionization of CsI Berkowitz, 1969. See also Bulewicz, Phillips, et al., 1961, Scheer and Fine, 1962. |
| 6 | From photoionization mass-spectrometry Berkowitz, 1969. The adiabatic ionization potential from photoelectron spectroscopy Berkowitz, Dehmer, et al., 1973, Potts, Williams, et al., 1974 is 7.10 eV; the first and second vertical potentials are 7.54 and 8.46 eV (average values). |
| 7 | μel = 11.69D Story and Hebert, 1976 (molecular beam electric deflection) Story and Hebert, 1976; eqQ(127I) = -[14.28 + 2.10(v+1/2)] MHz, |eqQ(133Cs)| ≤ 1 MHz Hoeft, Tiemann, et al., 1972; |gJ| < 0.0036 μN Honerjager and Tischer, 1973. |
| 8 | From the photoionization data of Berkowitz, 1969. Using 7.10 instead of 7.25 eV for I.P.(CsI) (see 6) would increase this value to 0.36 eV. |
References
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering 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.
Viswanathan and Hilpert, 2010
Viswanathan, R.; Hilpert, K.,
Mass Spectrometric Study of the Vaporization of Cesium Iodide and Thermochemistry of (CsI)2(g) and (CsI)3(g),
Berichte der Bunsengesellschaft für physikalische Chemie, 2010, 88, 2, 125-131, https://doi.org/10.1002/bbpc.19840880210
. [all data]
Pankajavalli, Mallika, et al., 1998
Pankajavalli, R.; Mallika, C.; Sreedharan, O.M.; Premila, M.; Gopalan, Padma,
Vapour pressure of C60 by a transpiration method using a horizontal thermobalance,
Thermochimica Acta, 1998, 316, 1, 101-108, https://doi.org/10.1016/S0040-6031(98)00304-9
. [all data]
Cordfunke, 1986
Cordfunke, E.H.P.,
Thermodynamic properties of CSI. II. vapour pressures and thermochemical properties of CsI(g) and Cs2I2(g),
Thermochimica Acta, 1986, 108, 45-55, https://doi.org/10.1016/0040-6031(86)85076-6
. [all data]
Venugopal, Prasad, et al., 1985
Venugopal, V.; Prasad, R.; Sood, D.D.,
Vaporisation thermodynamics of caesium iodide and caesium chromate,
Journal of Nuclear Materials, 1985, 130, 115-121, https://doi.org/10.1016/0022-3115(85)90300-9
. [all data]
Wang, Wang, et al., 2010
Wang, Y.L.; Wang, X.B.; Xing, X.P.; Wei, F.; Li, J.; Wang, L.S.,
Photoelectron Imaging and Spectroscopy of MI2- (M = Cs, Cu, Au): Evolution from Ionic to Covalent Bonding,
J. Phys. Chem. A, 2010, 114, 42, 11244-11251, https://doi.org/10.1021/jp103173d
. [all data]
Gusarov, Gorokhov, et al., 1979
Gusarov, A.V.; Gorokhov, L.N.; Pyatenko, A.T.; Sidorova, I.V.,
Negative ions in the vapors of inorganic compounds,
Adv. Mass Spectrom., 1979, 8, 262. [all data]
Miller, Leopold, et al., 1986
Miller, T.M.; Leopold, D.G.; Murray, K.K.; Lineberger, W.C.,
Electron Affinities of the Alkali Halides and the Structure of their Negative Ions,
J. Chem. Phys., 1986, 85, 5, 2368, https://doi.org/10.1063/1.451091
. [all data]
Benson, Novak, et al., 1987
Benson, J.M.; Novak, I.; Potts, A.W.,
Photoelectron spectroscopy of the caesium halides using synchrotron radiation,
J. Phys. B:, 1987, 20, 6257. [all data]
Viswanathan and Hilpert, 1984
Viswanathan, R.; Hilpert, K.,
Mass spectrometric study of the vaporization of cesium iodide and thermochemistry of (CsI)2(g) and (CsI)3(g),
Ber. Bunsen-Ges. Phys. Chem., 1984, 88, 125. [all data]
Emons, Horlbeck, et al., 1982
Emons, H.-H.; Horlbeck, W.; Kiessling, D.,
Massenspektrometrische untersuchung der gasphase uber alkalimetalliodiden,
Z. Anorg. Allg. Chem., 1982, 488, 212. [all data]
Potts and Price, 1977
Potts, A.W.; Price, W.C.,
Photoelectron studies of ionic materials using molecular beam techniques,
Phys. Scr., 1977, 16, 191. [all data]
Smith and Pong, 1975
Smith, J.A.; Pong, W.,
Ultraviolet photoelectron spectra of cesium halides,
Phys. Rev. B:, 1975, 12, 5931. [all data]
Potts, Williams, et al., 1974
Potts, A.W.; Williams, T.A.; Price, W.C.,
Photoelectron spectra and electronic structure of diatomic alkali halides,
Proc. Roy. Soc. London A, 1974, 341, 147. [all data]
Berkowitz, Dehmer, et al., 1973
Berkowitz, J.; Dehmer, J.L.; Walker, T.E.H.,
PES of high-temperature vapors. IV. The cesium halides. Effect of spin-orbit interaction on the photoelectron and mass spectra of the alkali halides,
J. Chem. Phys., 1973, 59, 3645. [all data]
Berkowitz, 1969
Berkowitz, J.,
Photoionization of high-temperature vapors. V. Cesium halides; chemical shift of autoionization,
J. Chem. Phys., 1969, 50, 3503. [all data]
Timoshenko and Akopyan, 1974
Timoshenko, M.M.; Akopyan, M.E.,
Photoelectron spectra of cesium halides,
High Energy Chem., 1974, 8, 175, In original 211. [all data]
Goodman, Allen, et al., 1974
Goodman, T.D.; Allen, J.D., Jr.; Cusachs, L.C.; Schweitzer, G.K.,
The photoelectron spectra of gaseous alkali halides,
J. Electron Spectrosc. Relat. Phenom., 1974, 3, 289. [all data]
Platel, 1965
Platel, G.,
Mesures des potentials d'apparition des ions obtenus par impact electronique dans la phase vapeur des iodures alcalins et des melanges LiI-MI,
J. Chim. Phys., 1965, 62, 1176. [all data]
Geiger and Pfeiffer, 1968
Geiger, J.; Pfeiffer, H.-C.,
Untersuchung der Anregung innerer Elektronen von Alkalihalogenidmolekulen im Energieverlustspektrum von 25 keV-Elektronen,
Z. Phys., 1968, 208, 105. [all data]
Schmidt-Ott, 1931
Schmidt-Ott, H.D.,
Uber kontinuierliche absorptionsspektra der gasformigen alkalihalogenide im ultraviolett,
Z. Phys., 1931, 69, 724. [all data]
Barrow and Caunt, 1953
Barrow, R.F.; Caunt, A.D.,
The ultra-violet absorption spectra of some gaseous alkali-metal halides and the dissociation energy of fluorine,
Proc. R. Soc. London A, 1953, 219, 120. [all data]
Davidovits and Brodhead, 1967
Davidovits, P.; Brodhead, D.C.,
Ultraviolet absorption cross sections for the alkali halide vapors,
J. Chem. Phys., 1967, 46, 2968. [all data]
Sommermeyer, 1929
Sommermeyer, K.,
Ein neues spektrum der gasformigen alkalihalogenide und seine deutung,
Z. Phys., 1929, 56, 548. [all data]
Oldenborg, Gole, et al., 1974
Oldenborg, R.C.; Gole, J.L.; Zare, R.N.,
Chemiluminescent spectra of alkali-halogen reactions,
J. Chem. Phys., 1974, 60, 4032. [all data]
Honig, Stitch, et al., 1953
Honig, A.; Stitch, M.L.; Mandel, M.,
Microwave spectra of CsF, CsCl, and CsBr,
Phys. Rev., 1953, 92, 901. [all data]
Rusk and Gordy, 1962
Rusk, J.R.; Gordy, W.,
Millimeter wave molecular beam spectroscopy: alkali bromides and iodides,
Phys. Rev., 1962, 127, 817. [all data]
Honerjager and Tischer, 1974
Honerjager, R.; Tischer, R.,
Mikrowellenrotationsspektren der Molekeln CsF, CsCl, CsBr und CsI,
Z. Naturforsch. A, 1974, 29, 819. [all data]
Rice and Klemperer, 1957
Rice, S.A.; Klemperer, W.,
Spectra of the alkali halides. II. The infrared spectra of the sodium and potassium halides, RbCl, and CsCl,
J. Chem. Phys., 1957, 27, 573. [all data]
Brewer and Brackett, 1961
Brewer, L.; Brackett, E.,
The dissociation energies of gaseous alkali halides,
Chem. Rev., 1961, 61, 425. [all data]
Bulewicz, Phillips, et al., 1961
Bulewicz, E.M.; Phillips, L.F.; Sugden, T.M.,
Determination of dissociation constants and heats of formation of simple molecules by flame photometry. Part 8. Stabilities of the gaseous diatomic halides of certain metals,
Trans. Faraday Soc., 1961, 57, 921. [all data]
Scheer and Fine, 1962
Scheer, M.D.; Fine, J.,
Entropies, heats of sublimation, and dissociation energies of the cesium halides,
J. Chem. Phys., 1962, 36, 1647. [all data]
Story and Hebert, 1976
Story, T.L., Jr.; Hebert, A.J.,
Dipole moments of KI, RbBr, RbI, CsBr, and CsI by the electric deflection method,
J. Chem. Phys., 1976, 64, 855. [all data]
Hoeft, Tiemann, et al., 1972
Hoeft, J.; Tiemann, E.; Torring, T.,
Hyperfeinstruktur von CsJ,
Z. Naturforsch. A, 1972, 27, 1017. [all data]
Honerjager and Tischer, 1973
Honerjager, R.; Tischer, R.,
Hochtemperatur-Mikrowellenspektrometer fur Zeeman-Effekt-Messungen an diamagnetischen Molekeln. gJ - Faktor von TlF, CsF, CsCl, CsBr, CsI und Anistropie der magnetischen suszeptibilitat von TlF, CsF und CsCl,
Z. Naturforsch. A, 1973, 28, 458. [all data]
Notes
Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Constants of diatomic molecules, References
- Symbols used in this document:
AE Appearance energy EA Electron affinity ΔrH° Enthalpy of reaction at standard conditions ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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