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.
Information on this page:
Other data available:
Data at other public NIST sites:
Options:
- Switch to calorie-based units

Constants of diatomic molecules

Data compiled by: Klaus P. Huber and Gerhard H. Herzberg

Data collected through November, 1976

Symbols used in the table of constants
Symbol	Meaning
State	electronic state and / or symmetry symbol
T_e	minimum electronic energy (cm^-1)
ω_e	vibrational constant – first term (cm^-1)
ω_ex_e	vibrational constant – second term (cm^-1)
ω_ey_e	vibrational constant – third term (cm^-1)
B_e	rotational constant in equilibrium position (cm^-1)
α_e	rotational constant – first term (cm^-1)
γ_e	rotation-vibration interaction constant (cm^-1)
D_e	centrifugal distortion constant (cm^-1)
β_e	rotational constant – first term, centrifugal force (cm^-1)
r_e	internuclear distance (Å)
Trans.	observed transition(s) corresponding to electronic state
ν₀₀	position of 0-0 band (units noted in table)

Diatomic constants for ¹³³Cs¹²⁷I
State	T_e	ω_e	ω_ex_e	B_e	α_e	D_e	β_e	r_e
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
X ¹Σ⁺	↳Honig, Stitch, et al., 1953; Rusk and Gordy, 1962; Honerjager and Tischer, 1974

Notes

Derived from the rotational constants Honerjager and Tischer, 1974. See also Barrow and Caunt, 1953, Rice and Klemperer, 1957.

α_v= +4.89E-8(v+1/2)² + 1.14E-10(v+1/2)³ Honerjager and Tischer, 1974.

Also higher order constants Honerjager and Tischer, 1974.

Microwave sp. 7

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.

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).

μ_el = 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 μ_N Honerjager and Tischer, 1973.

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, Constants of diatomic molecules, Notes

Berkowitz, 1969
Berkowitz, J., Photoionization of high-temperature vapors. V. Cesium halides; chemical shift of autoionization, J. Chem. Phys., 1969, 50, 3503. [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]

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]

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]

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, Constants of diatomic molecules, References

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
Customer support for NIST Standard Reference Data products.