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Slater's rules
Introduction
Slater’s Rules are a set of rules devised by John C. Slater that give an approximate estimate of effective nuclear charge on an electron (Z*).
<math>Z*=Z-S</math>
where S is the screening constant.
The system involves the two following steps:
1.Arrange sets according to principle quantum number, ignoring filling order and keeping ns and np together
i.e [1s] [2s,2p] [3s,3p] [3d] [4s,4p] [4d] [4f]
2.Using the table, calculate the contributions to S (the screening constant) for electrons in each set.
| Set | Electrons in Higher Sets | Remaining Electrons in Same set | All electrons in lower sets | Electrons in set(s) with quantum number n-1 | Electrons in all sets with quantum number <n-1 |
|---|---|---|---|---|---|
| [1s] | 0 | 0.3 | N/A | N/A | N/A |
| [ns,np] | 0 | 0.35 | 0.85 | 1 | |
| [nd] or [nf] | 0 | 0.35 | 1 |