52

55cs 1s2 2s2 2p6 3s2 3p6 4d10 4s2 4p6 4d10 5s2 5p6 6s
1s2 Zeff=55-0.35=54.65
2s22p6 55-4.15=50.85
3s23p6 55-11.25=50.85
3d10 55-21.15=33.85
4s2sp6 55-24.35=30.65
4d10 55-36x1.00-9x0.35=55-39.15=15.85
5s25p6 55-28x1.00-18x0.85-7x0.35=55-45.75=9.25
6s 55-46x1.00-8x0.85=55-52.8=3.2
Sum of Zeff=54.65+50.85+4/9x43.75+5/9x33.85+1/4x30.65
+5/16x15.85+4/25x9.25+1/72x3.2
=157.87
Dia curtium=3.552x10-5x157.4=5.60x10-3