chromium

• Formula: Cr
• Molecular weight: 51.9961
• IUPAC Standard InChI: InChI=1S/Cr Copy

  
• IUPAC Standard InChIKey: VYZAMTAEIAYCRO-UHFFFAOYSA-N Copy
• CAS Registry Number: 7440-47-3
• Chemical structure:
  This structure is also available as a 2d Mol file
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry 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
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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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Phase change 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.

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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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 evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
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 Cr⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

References

Go To: Top, Condensed phase thermochemistry data, Phase change 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.

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

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [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]

Bilodeau, Scheer, et al., 1998
Bilodeau, R.C.; Scheer, M.; Haugen, H.K., Infrared Laser Photodetachment of Transition Metal Negative Ions: Studies on Cr-, Mo-, Cu-, and Ag-, J. Phys. B: Atom. Mol. Opt. Phys., 1998, 31, 17, 3885-3891, https://doi.org/10.1088/0953-4075/31/17/013 . [all data]

Bengali, Casey, et al., 1992
Bengali, A.A.; Casey, S.M.; Cheng, C.-L.; Dick, J.P.; Fenn, T.; Villaalta, P.W.; Leopold, D.G., Negative Ion Photoelectron Spectroscopy of Coordinatively Unsaturated Group VI Metal Carbonyls: Cr(CO)3, Mo(CO)3, and W(CO)3, J. Am. Chem. Soc., 1992, 114, 13, 5257, https://doi.org/10.1021/ja00039a043 . [all data]

Feigerle, Corderman, et al., 1981
Feigerle, C.S.; Corderman, R.R.; Bobashev, S.V.; Lineberger, W.C., Binding Energies and Structure of Transition Metal Negative Ions, J. Chem. Phys., 1981, 74, 3, 1580, https://doi.org/10.1063/1.441289 . [all data]

Feldmann, Rackwitx, et al., 1977
Feldmann, D.; Rackwitx, R.; Heinicke, E.; Kaiser, H.J., Photodetachment of Some Atomic Negative Ions: P-, As-, Sb-, Te-, Cr-, Ni-, Z. Physik A., 1977, 282, 2, 143-148, https://doi.org/10.1007/BF01408156 . [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]

Sugar and Corliss, 1985
Sugar, J.; Corliss, C., Atomic energy levels of the iron period elements: Potassium through nickel, J. Phys. Chem. Ref. Data, 1985, 14. [all data]

Balducci, Gigli, et al., 1981
Balducci, G.; Gigli, G.; Guido, M., Dissociation energies of the molecules CrPO₂(g) and CoO(g) by high-temperature mass spectrometry, J. Chem. Soc. Faraday Trans. 2, 1981, 77, 1107. [all data]

Dyke, Fayad, et al., 1979
Dyke, J.M.; Fayad, N.K.; Morris, A.; Trickle, I.R., Gas-phase He I photoelectron spectra of some transition metals: Cu, Ag, Au, Cr and Mn, J. Phys. B:, 1979, 12, 2985. [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

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• Symbols used in this document:
  

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