Main energy levels (n) are split into sub-levels (s, p, d, f). Each sub-level contains orbitals - regions of space where there is a high probability of finding an electron. Each individual orbital holds a maximum of 2 electrons.
Orbital Definition
Atomic Orbitals
An atomic orbital is a region of space around the nucleus where there is a high probability of finding an electron (typically defined as >90% probability). Each individual orbital can hold a maximum of two electrons with opposite spins.
s-orbitals
Spherical Shape
- Found in all levels (n=1+).
- 1 orbital per sublevel.
- Max 2 electrons.
Sublevel Capacity
Sublevel Structure & Capacities
- s sublevel: 1 orbital → max 2 electrons
- p sublevel: 3 degenerate orbitals (px, py, pz) → max 6 electrons
- d sublevel: 5 degenerate orbitals → max 10 electrons
- f sublevel: 7 degenerate orbitals → max 14 electrons
p-orbitals
Dumbbell Shape
- Found in n=2 onwards.
- 3 orbitals per sublevel (\(p_x, p_y, p_z\)).
- Max 6 electrons.
Total Sublevel Capacities
s-sublevel2 e⁻
p-sublevel6 e⁻
d-sublevel10 e⁻
f-sublevel14 e⁻
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