iron

• Formula: Fe
• Molecular weight: 55.845
• IUPAC Standard InChI: InChI=1S/Fe Copy

  
• IUPAC Standard InChIKey: XEEYBQQBJWHFJM-UHFFFAOYSA-N Copy
• CAS Registry Number: 7439-89-6
• 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
  • 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:
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  • 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

Go To: Top, 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.

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, 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:
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 Fe⁺ (ion structure unspecified)

Electron affinity determinations

Ionization energy determinations

References

Go To: Top, 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.

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

Miller, Miller, et al., 1993
Miller, A.E.S.; Miller, T.M.; Morris, R.A.; Viggiano, A.A.; Vandoren, J.M.; Paulson, J.F., Reactions of Fe- with Acids - Gas-Phase Acidity and Bond Energy of FeH, Int. J. Mass Spectrom. Ion Proc., 1993, 123, 3, 205, https://doi.org/10.1016/0168-1176(93)87099-E . [all data]

Leopold and Lineberger, 1986
Leopold, D.G.; Lineberger, W.C., A study of the low-lying electronic states of Fe₂ and Co₂ by negative ion photoelectron spectroscopy, J. Chem. Phys., 1986, 85, 51. [all data]

Engelking and Lineberger, 1979
Engelking, P.C.; Lineberger, W.C., Laser Photoelectron Spectroscopy of Fe^-: the Electron Affinity of Iron and the Nonstatistical Fine Structure Detachment Intensities at 488 nm, Phys. Rev. A, 1979, 19, 1, 149, https://doi.org/10.1103/PhysRevA.19.149 . [all data]

Engelking and Lineberger, 1976
Engelking, P.C.; Lineberger, W.C., Electron Affinity of Atomic Iron and Some Iron Compounds Mearsured by Photoelectron Spectroscopy, Bull. Am. Phys. Soc., 1976, 21, 1263. [all data]

Compton and Stockdale, 1976
Compton, R.N.; Stockdale, J.A.D., Formation of gas phase negative ions in Fe(CO)₅ and Ni(CO)₄, Int. J. Mass Spectrom. Ion Phys., 1976, 22, 47. [all data]

Russell, Solouki, et al., 1995
Russell, D.H.; Solouki, T.; Oriedo, J.V.B., Collisional relaxation of metastable electronic states of Fe⁺, J. Am. Soc. Mass Spectrom., 1995, 6, 543. [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]

Kelly, 1987
Kelly, R.L., Atomic and ionic spectrum lines of hydrogen through kryton, J. Phys. Chem. Ref. Data, 1987, 16. [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]

Dyke, Gravenor, et al., 1982
Dyke, J.M.; Gravenor, B.W.J.; Lewis, R.A.; Morris, A., Gas-phase high temperature photoelectron spectroscopy: An investigation of the transition metals iron, cobalt, and nickel, J. Phys. B:, 1982, 15, 4523. [all data]

Clements and Sale, 1976
Clements, P.J.; Sale, F.R., A mass spectrometric study of nickel tetracarbonyl, iron pentacarbonyl and binary mixtures of these compounds, Metall. Trans. B:, 1976, 7, 171. [all data]

Hildenbrand, 1975
Hildenbrand, D.L., Thermochemistry of molecular FeO, FeO⁺ and FeO₂, Chem. Phys. Lett., 1975, 34, 352. [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, Condensed phase thermochemistry data, Gas phase ion energetics data, References

• 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)
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions

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