Electronic configuration of gold

Electrons in each shell

Gold has 79 electrons arranged as 2, 8, 18, 32, 18, 1 across 6 shells, which is why it sits in period 6.

How to write it

Start from the previous noble gas core, written in square brackets, then add the remaining electrons in filling order. For gold that gives [Xe] 4f¹⁴ 5d¹⁰ 6s¹.

Exception to the Aufbau rule. Filling orbitals in order would give 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d⁹, but the real configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s¹ because a completely filled 5d¹⁰ is extra stable, just like copper and silver.

Gold at a glance

Other elements in group 11