PHYSICS · Multi-part · Fermi University Physics · Atomic, Molecular & Optical Physics · Many-electron atoms and the periodic table · Many-electron atoms and the periodic table
Deriving the Spectrum, Ch Many-electron terms, levels and Hund's rules
Problem
Atomic sulfur has ground configuration 3p4, which by the hole rule gives the same terms as 3p2: 3P, 1D, 1S, but with the fine structure of 3P inverted. The measured levels are 3P2=0cm−1 (ground), 3P1=396.055cm−1, 3P0=573.640cm−1, 1D2=9238.609cm−1, 1S0=22179.954cm−1.
((a)) Compute the (2J+1)-weighted centroid of the 3P term.
((b)) Test the Slater-integral prediction E(1D)−E(3P)E(1S)−E(1D)=23 using the centroid, and compare with oxygen's measured value of 1.14 for the analogous 2p4 configuration.
((c)) Test the Lande interval rule on the (inverted) 3P term: compute the two intervals EJ=1−EJ=0 and EJ=2−EJ=1, their ζLS estimates, and the ratio of interval magnitudes. Compare with oxygen's measured ratio of 2.30.