Ground States and Ionization Energies: Fe

NIST Atomic Spectroscopic Database

Ground States and Ionization Energies: Fe

Iron, Z = 26

Fe I

Fe I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d⁶4s² ⁵D₄

Ionization energy 63737 ± 1 cm^-¹

References on Energy Levels, Transition Probabilities

Fe II

Mn I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d⁶4s ⁶D_9/2

Ionization energy 130563 ± 10 cm^-¹

References on Energy Levels, Transition Probabilities

Fe III

Cr I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d⁶ ⁵D₄

Ionization energy 247220 ± 100 cm^-¹

References on Energy Levels, Transition Probabilities

Fe IV

V I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d⁵ ⁶S_5/2

Ionization energy 442000 ± 1000 cm^-¹

References on Energy Levels, Transition Probabilities

Fe V

Ti I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d⁴ ⁵D₀

Ionization energy 605000 ± 1200 cm^-¹

References on Energy Levels, Transition Probabilities

Fe VI

Sc I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d³ ⁴F_3/2

Ionization energy 799000 ± 2000 cm^-¹

References on Energy Levels, Transition Probabilities

Fe VII

Ca I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d² ³F₂

Ionization energy 1008000 ± 100 cm^-¹

References on Energy Levels, Transition Probabilities

Fe VIII

K I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶3d ²D_3/2

Ionization energy 1218380 ± 100 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe IX

Ar I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁶ ¹S₀

Ionization energy 1884000 ± 3000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe X

Cl I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁵ ²Pº_3/2

Ionization energy 2114000 ± 1000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XI

S I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p⁴ ³P₂

Ionization energy 2341000 ± 5000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XII

P I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p³ ⁴Sº_3/2

Ionization energy 2668000 ± 5000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XIII

Si I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p² ³P₀

Ionization energy 2912000 ± 6000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XIV

Al I isoelectronic sequence

Ground state 1s²2s²2sp3s²3p ²Pº_1/2

Ionization energy 3163000 ± 6000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XV

Mg I isoelectronic sequence

Ground state 1s²2s²2sp3s² ¹S₀

Ionization energy 3686000 ± 20000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XVI

Na I isoelectronic sequence

Ground state 1s²2s²2sp3s ²S_1/2

Ionization energy 3946280 ± 300 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XVII

Ne I isoelectronic sequence

Ground state 1s²2s²2p⁶ ¹S₀

Ionization energy 10180000 ± 8000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XVIII

F I isoelectronic sequence

Ground state 1s²2s²2p⁵ ²Pº_3/2

Ionization energy 10985000 ± 30000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XIX

O I isoelectronic sequence

Ground state 1s²2s²2p⁴ ³P₂

Ionization energy 11850000 ± 30000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XX

N I isoelectronic sequence

Ground state 1s²2s²2p³ ⁴Sº_3/2

Ionization energy 12708000 ± 4000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XXI

C I isoelectronic sequence

Ground state 1s²2s²2p² ³P₀

Ionization energy 13620000 ± 30000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XXII

B I isoelectronic sequence

Ground state 1s²2s²2p ²Pº_1/2

Ionization energy 14510000 ± 30000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XXIII

Be I isoelectronic sequence

Ground state 1s²2s² ¹S₀

Ionization energy 15797000 ± 30000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XXIV

Li I isoelectronic sequence

Ground state 1s²2s ²S_1/2

Ionization energy 16500000 ± 4000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XXV

He I isoelectronic sequence

Ground state 1s² ¹S₀

Ionization energy 71203000 ± 14000 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

Fe XXVI

H I isoelectronic sequence

Ground state 1s ²S_1/2

Ionization energy 74829600 ± 300 cm^-¹

References on Energy Levels, Wavelengths, Transition Probabilities

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