Cesium

• Formula: Cs
• Molecular weight: 132.9054519
• IUPAC Standard InChI: InChI=1S/Cs Copy

  
• IUPAC Standard InChIKey: TVFDJXOCXUVLDH-UHFFFAOYSA-N Copy
• CAS Registry Number: 7440-46-2
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Caesium
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Ion clustering data
• Data at other public NIST sites:
  • NIST Atomic Spectra Database - Lines Holdings (on physics web site)
  • NIST Atomic Spectra Database - Levels Holdings (on physics web site)
  • NIST Atomic Spectra Database - Ground states and ionization energies (on physics web site)
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
• Options:
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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Gas phase thermochemistry data

Go To: Top, 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.

Gas Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Condensed phase 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.

Liquid Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Solid Phase Heat Capacity (Shomate Equation)

C_p° = 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
    C_p = heat capacity (cal/mol*K)
    H° = standard enthalpy (kcal/mol)
    S° = standard entropy (cal/mol*K)
    t = temperature (K) / 1000.

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Gas phase ion energetics data

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 evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
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

View reactions leading to Cs⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Cox, Wagman, et al., 1984
Cox, J.D.; Wagman, D.D.; Medvedev, V.A., CODATA Key Values for Thermodynamics, Hemisphere Publishing Corp., New York, 1984, 1. [all data]

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]

Scheer, Tho/gersen, et al., 1998
Scheer, M.; Tho/gersen, J.; Bilodeau, R.C.; Brodie, C.A.; Haugen, H.K., Experimental Evidence that the 6s6p2Pj States of Cs- are Shape Resonances, Phys. Rev. Lett., 1998, 80, 4, 684, https://doi.org/10.1103/PhysRevLett.80.684 . [all data]

Slater, Read, et al., 1978
Slater, J.; Read, F.H.; Novick, S.E.; Lineberger, W.C., Alkali Negative Ions. III. Multichannel Photodetachment of Cs- and K-, Phys. Rev. A, 1978, 17, 1, 201, https://doi.org/10.1103/PhysRevA.17.201 . [all data]

Patterson, Hotop, et al., 1974
Patterson, T.A.; Hotop, H.; Kasdan, A.; Norcross, D.W.; Lineberger, W.C., Resonances in Alkali Negative-Ion Photodetachment and Electron Affinities of the Corresponding Neutrals, Phys. Rev. Lett., 1974, 32, 5, 189, https://doi.org/10.1103/PhysRevLett.32.189 . [all data]

Lide, 1992
Lide, D.R. (Editor), Ionization potentials of atoms and atomic ions in Handbook of Chem. and Phys., 1992, 10-211. [all data]

Busse and Weil, 1982
Busse, B.; Weil, K.G., Mass spectrometric studies on the vapour phase composition over solid and fused Cs₃Sb, Ber. Bunsen-Ges. Phys. Chem., 1982, 86, 93. [all data]

Williams and Potts, 1976
Williams, T.A.; Potts, A.W., Complexities in the HeI photoelectron spectra of alkali metal vapours, J. Electron Spectrosc. Relat. Phenom., 1976, 8, 331. [all data]

Nygaard and Hahn, 1974
Nygaard, K.J.; Hahn, Y.B., Ion fluorescene in cesium, Physica, 1974, 75, 333. [all data]

Moore, 1970
Moore, C.E., Ionization potentials and ionization limits derived from the analyses of optical spectra, Natl. Stand. Ref. Data Ser., (U.S. Natl. Bur. Stand.), 1970, 34, 1. [all data]

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  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
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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