a.Screen (shielding)constant Slater's rules for the prediction of o for an electron: 1.Group electron configuration as follows: (1s)2s,2p)(3s,3p)(3d(4s,4p)(4d(4f(5s,5p)etc 2.Electrons in the right shells (in higher subshells and shells)of an electron do not shield it. 3.For ns or np valence electrons: a)each other electron in the same group contributes 0.35 (0.30for1s) b)each electron in an n-1 group(s)contribute 0.85 c)each electron in an n-2 or lower group contributes 1.00 4.For nd or nf valence electrons: a)each other electron in the same group contributes 0.35 b)each electron in a lower group (to the left)contributes 1.00 The basis of Slater's rules for o s and p orbitals have better "penetration to the nucleus thar d (or f)orbitals for any given value of n i.e.there is a greater probability of s and p electrons being Charge does near the nucleus not contribute This means: 1.ns and np orbitals completely shield nd orbitals 2.(n-1)s and p orbitals don't completely shield n s and p orbitalsa. Screen (shielding) constant Slater’s rules for the prediction of σ for an electron: 1. Group electron configuration as follows: (1s)(2s,2p)(3s,3p)(3d)(4s,4p)(4d)(4f)(5s,5p) etc. 2. Electrons in the right shells (in higher subshells and shells) of an electron do not shield it. 3. For ns or np valence electrons: a) each other electron in the same group contributes 0.35 (0.30 for 1s) b) each electron in an n-1 group(s) contribute 0.85 c) each electron in an n-2 or lower group contributes 1.00 4. For nd or nf valence electrons: a) each other electron in the same group contributes 0.35 b) each electron in a lower group (to the left) contributes 1.00 The basis of Slater’s rules for σ s and p orbitals have better “penetration” to the nucleus than d (or f) orbitals for any given value of n i.e. there is a greater probability of s and p electrons being near the nucleus This means: 1. ns and np orbitals completely shield nd orbitals 2. (n-1) s and p orbitals don’t completely shield n s and p orbitals