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:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • 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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Gas 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.

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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/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 (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/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 (bar)
    T = temperature (K)

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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 as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
MS - José A. Martinho Simões

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: Cr⁺ + Cr = (Cr⁺ • Cr)

Enthalpy of reaction

(CAS Reg. No. 136056-49-0 • 4294967295) +  = CAS Reg. No. 136056-49-0

By formula: (CAS Reg. No. 136056-49-0 • 4294967295Cr) + Cr = CAS Reg. No. 136056-49-0

 (cr) = 6 (g) +  (cr)

By formula: C₆CrO₆ (cr) = 6CO (g) + Cr (cr)

(CAS Reg. No. 135774-12-8 • 4294967295) +  = CAS Reg. No. 135774-12-8

By formula: (CAS Reg. No. 135774-12-8 • 4294967295Cr) + Cr = CAS Reg. No. 135774-12-8

C₁₄H₁₀CrN₂O₄ (cr) = 2 (g) + 4 (g) +  (cr)

By formula: C₁₄H₁₀CrN₂O₄ (cr) = 2C₄H₄N₂ (g) + 4CO (g) + Cr (cr)

( • 10) +  = ( • 11)

By formula: (Cr⁺ • 10Cr) + Cr = (Cr⁺ • 11Cr)

Enthalpy of reaction

( • 11) +  = ( • 12)

By formula: (Cr⁺ • 11Cr) + Cr = (Cr⁺ • 12Cr)

Enthalpy of reaction

( • 12) +  = ( • 13)

By formula: (Cr⁺ • 12Cr) + Cr = (Cr⁺ • 13Cr)

Enthalpy of reaction

( • 13) +  = ( • 14)

By formula: (Cr⁺ • 13Cr) + Cr = (Cr⁺ • 14Cr)

Enthalpy of reaction

( • 14) +  = ( • 15)

By formula: (Cr⁺ • 14Cr) + Cr = (Cr⁺ • 15Cr)

Enthalpy of reaction

( • 15) +  = ( • 16)

By formula: (Cr⁺ • 15Cr) + Cr = (Cr⁺ • 16Cr)

Enthalpy of reaction

( • 16) +  = ( • 17)

By formula: (Cr⁺ • 16Cr) + Cr = (Cr⁺ • 17Cr)

Enthalpy of reaction

( • 17) +  = ( • 18)

By formula: (Cr⁺ • 17Cr) + Cr = (Cr⁺ • 18Cr)

Enthalpy of reaction

( • 18) +  = ( • 19)

By formula: (Cr⁺ • 18Cr) + Cr = (Cr⁺ • 19Cr)

Enthalpy of reaction

( • 19) +  = ( • 20)

By formula: (Cr⁺ • 19Cr) + Cr = (Cr⁺ • 20Cr)

Enthalpy of reaction

( • 9) +  = ( • 10)

By formula: (Cr⁺ • 9Cr) + Cr = (Cr⁺ • 10Cr)

Enthalpy of reaction

( • 2) +  = ( • 3)

By formula: (Cr⁺ • 2Cr) + Cr = (Cr⁺ • 3Cr)

Enthalpy of reaction

( • 3) +  = ( • 4)

By formula: (Cr⁺ • 3Cr) + Cr = (Cr⁺ • 4Cr)

Enthalpy of reaction

( • 4) +  = ( • 5)

By formula: (Cr⁺ • 4Cr) + Cr = (Cr⁺ • 5Cr)

Enthalpy of reaction

( • 5) +  = ( • 6)

By formula: (Cr⁺ • 5Cr) + Cr = (Cr⁺ • 6Cr)

Enthalpy of reaction

( • 6) +  = ( • 7)

By formula: (Cr⁺ • 6Cr) + Cr = (Cr⁺ • 7Cr)

Enthalpy of reaction

( • 7) +  = ( • 8)

By formula: (Cr⁺ • 7Cr) + Cr = (Cr⁺ • 8Cr)

Enthalpy of reaction

( • 8) +  = ( • 9)

By formula: (Cr⁺ • 8Cr) + Cr = (Cr⁺ • 9Cr)

Enthalpy of reaction

( • ) +  = ( • 2)

By formula: (Cr⁺ • Cr) + Cr = (Cr⁺ • 2Cr)

Enthalpy of reaction

(CAS Reg. No. 64911-49-5 • 4294967295) +  = CAS Reg. No. 64911-49-5

By formula: (CAS Reg. No. 64911-49-5 • 4294967295Cr) + Cr = CAS Reg. No. 64911-49-5

CrF₁₈P₆ (cr) =  (cr) + 6 (g)

By formula: CrF₁₈P₆ (cr) = Cr (cr) + 6F₃P (g)

Gas phase ion energetics data

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

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]

Houriet and Vulpius, 1989
Houriet, R.; Vulpius, T., Formation of Metal Cluster Ions by Gas - Phase Ion - Molecule Reactions: the Bond Energies of Cr2+ and Mn2+, Chem. Phys. Lett., 1989, 154, 5, 454, https://doi.org/10.1016/0009-2614(89)87130-1 . [all data]

Hilpert and Ruthardt, 1987
Hilpert, K.; Ruthardt, K., Determination of the dissociation energy of the Cr₂ molecule, Ber. Bunsen-Ges. Phys. Chem., 1987, 91, 724. [all data]

Armentrout and Kickel, 1994
Armentrout, P.B.; Kickel, B.L., Gas Phase Thermochemistry of Transition Metal Ligand Systems: Reassessment of Values and Periodic Trends, in Organometallic Ion Chemistry, B. S. Freiser, ed, 1994. [all data]

Boltalina, Borshchevskii, et al., 1991
Boltalina, O.V.; Borshchevskii, A.Y.; Sidorov, L.N., Thermochemistry of Chromium Gaseous Fluorides and Their Negative Ions, Zh. Fiz. Khim. SSSR, 1991, 65, 884. [all data]

Pramann and Rademann, 1999
Pramann, A.; Rademann, K., Mass-spectrometric study of formation and stability of manganese and manganese oxide cluster anions, Int. J. Mass Spectrom., 1999, 187, 673-683, https://doi.org/10.1016/S1387-3806(98)14197-0 . [all data]

Al-Takhin, Connor, et al., 1984
Al-Takhin, G.; Connor, J.A.; Skinner, H.A.; Zaharani-Moettar, M.T., J. Organomet. Chem., 1984, 260, 189. [all data]

Pittam, Pilcher, et al., 1975
Pittam, D.A.; Pilcher, G.; Barnes, D.S.; Skinner, H.A.; Todd, D., J. Less-Common Met., 1975, 42, 217. [all data]

Pedley and Rylance, 1977
Pedley, J.B.; Rylance, J., Computer Analysed Thermochemical Data: Organic and Organometallic Compounds, University of Sussex, Brigton, 1977. [all data]

Tel'noi and Rabinovich, 1977
Tel'noi, V.I.; Rabinovich, I.B., Russ. Chem. Rev., 1977, 46, 689. [all data]

Connor, Skinner, et al., 1972
Connor, J.A.; Skinner, H.A.; Virmani, Y., Microcalorimetric studies. Thermal decomposition and iodination of metal carbonyls, J. Chem. Soc., Faraday Trans. 1, 1972, 68, 0, 1754, https://doi.org/10.1039/f19726801754 . [all data]

Casey, Villata, et al., 1991
Casey, S.M.; Villata, P.W.; Bengali, A.A.; Cheng, C.-L.; Dick, J.P.; Fenn, P.T.; Leopold, D.G., A Study of Cr2 by Negative ion Photoelectron Spectroscopy, J. Am. Chem. Soc., 1991, 113, 17, 6688, https://doi.org/10.1021/ja00017a058 . [all data]

Casey and Leopold, 1993
Casey, S.M.; Leopold, D.G., Negative Ion Photoelectron Spectroscopy of Cr2, J. Phys. Chem., 1993, 97, 4, 816, https://doi.org/10.1021/j100106a005 . [all data]

Adedeji, Connor, et al., 1978
Adedeji, F.A.; Connor, J.A.; Demain, C.P.; Martinho Simões, J.A.; Skinner, H.A.; Zafarani- Moattar, M.T., J. Organometal. Chem., 1978, 149, 333. [all data]

Wenthold, Gunion, et al., 1996
Wenthold, P.G.; Gunion, R.F.; Lineberger, W.C., Ultraviolet Negative-ion Photoelectron Spectroscopy of the Chromium Oxide Negative Ion, Chem. Phys. Lett., 1996, 258, 1-2, 101, https://doi.org/10.1016/0009-2614(96)00611-2 . [all data]

Brown and Connor, 1974
Brown, D.L.S.; Connor, J.A., Skinner, H. A. J. Chem. Soc., Faraday Trans. I, 1974, 70, 1649. [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]

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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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction 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
  T	Temperature
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

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