NIST Physical Measurement Laboratory Handbook of Basic Atomic Spectroscopic Data

[skip navigation] National Institute of Standards and Technology NIST Physical Measurement Laboratory Francium (Fr) 

Homepage - IntroductionFinding listSelect element by name.Select element by atomic number.Select element from periodic tableFrancium Atomic DataFrancium Strong LinesFrancium Neutral Atom Persistent Lines Francium Neutral Atom Energy LevelsFrancium Singly Ionized Persistent LinesFrancium Singly Ionized Energy LevelsFrancium References
Switch to Formatted Version

Atomic Data for Francium (Fr)

Atomic Number = 87

Atomic Weight = 223

Reference E95

Isotope    Mass        Abundance Spin Mag Moment
212Fr 211.996130 0* 5 223Fr 223.019733 some 3/2

*Note: Although not occuring naturally, the available spectroscopic data is for 212Fr.

Fr I  Ground State 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p67s  2S1/2
      Ionization energy  32848.872 cm-1 (4.072741 eV)   Ref. ABDJ90
Fr II Ground State 1s22s22p63s23p63d104s24p64d104f145s25p65d106s26p6  1S0