Gold Electron Configuration

Gold (Au, Z=79) has the anomalous configuration [Xe] 4f¹⁴ 5d¹⁰ 6s¹ — a fully filled d subshell gained by pulling one electron from 6s.

Use the Gold Electron Configuration

Z = 79 Au Gold

Gold — Electron Configuration

Atomic number 79 · Transition metal · Period 6, Group 11 · d-block

[Xe] 4f¹⁴ 5d¹⁰ 6s¹ 79 electrons 1 valence e⁻ Anomalous d¹⁰ s¹

Anomalous Configuration

Aufbau predicts [Xe] 4f¹⁴ 5d⁹ 6s², but gold adopts [Xe] 4f¹⁴ 5d¹⁰ 6s¹. A completely filled 5d subshell is more stable — one electron migrates from 6s to 5d. Copper and silver show the same d¹⁰ s¹ pattern for the same reason.

Subshell Breakdown

Subshell Type Electrons Max Capacity Notation
1s s orbital, shell n=1 2 2 1s²
2s s orbital, shell n=2 2 2 2s²
2p p orbitals, shell n=2 6 6 2p⁶
3s s orbital, shell n=3 2 2 3s²
3p p orbitals, shell n=3 6 6 3p⁶
3d d orbitals, shell n=3 10 10 3d¹⁰
4s s orbital, shell n=4 2 2 4s²
4p p orbitals, shell n=4 6 6 4p⁶
4d d orbitals, shell n=4 10 10 4d¹⁰
4f f orbitals, shell n=4 14 14 4f¹⁴
5s s orbital, shell n=5 2 2 5s²
5p p orbitals, shell n=5 6 6 5p⁶
5d d orbitals, shell n=5 (anomalous — filled by d¹⁰ s¹ effect) 10 10 5d¹⁰ anomalous
6s s orbital, shell n=6 (anomalous — single electron) 1 2 6s¹ anomalous
Total 79

Noble-Gas Shorthand

[Xe] 4f¹⁴ 5d¹⁰ 6s¹

[Xe] = 54 electrons in the filled xenon core.

Predicted (Aufbau)

[Xe] 4f¹⁴ 5d⁹ 6s²

Overridden — d¹⁰ s¹ is lower in energy than d⁹ s².

Shell Fill Summary

Shell 1 (n=1) — 1s² 2 / 2 electrons (100%)
Shell 2 (n=2) — 2s² 2p⁶ 8 / 8 electrons (100%)
Shell 3 (n=3) — 3s² 3p⁶ 3d¹⁰ 18 / 18 electrons (100%)
Shell 4 (n=4) — 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 32 / 32 electrons (100%)
Shell 5 (n=5) — 5s² 5p⁶ 5d¹⁰ 18 / 50 electrons (36%)
Shell 6 (n=6) — 6s¹ 1 / 72 electrons (1%)

Shell 5 holds 18 electrons here (5s + 5p + 5d); shell 6 holds the single anomalous 6s¹ electron.

Summary

Gold (Au) is element 79 and belongs to Period 6, Group 11 of the periodic table. Its ground-state configuration is [Xe] 4f¹⁴ 5d¹⁰ 6s¹ — anomalous because the Aufbau principle predicts [Xe] 4f¹⁴ 5d⁹ 6s², but a fully filled 5d subshell combined with a half-filled 6s provides extra stability. This tool presents the full subshell breakdown, an orbital box diagram, quantum numbers for the outermost electrons, and key atomic properties of gold.

How it works

  1. The Aufbau principle normally fills orbitals from lowest to highest energy.
  2. Gold's 79 electrons would predict [Xe] 4f¹⁴ 5d⁹ 6s², but the actual configuration is [Xe] 4f¹⁴ 5d¹⁰ 6s¹.
  3. A completely filled 5d¹⁰ subshell is energetically favored — it lowers electron repulsion and increases exchange energy.
  4. One electron migrates from 6s to 5d, giving a full d shell and a single s electron.
  5. Noble-gas notation replaces the xenon core [Xe] = 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ (54 electrons).
  6. The interactive tabs let you explore the configuration, orbital diagram, and element data separately.

Use cases

  • Quick reference for chemistry homework or exam prep on d-block anomalies.
  • Understand why gold has a single valence electron despite being a d-block metal.
  • Compare gold's anomalous configuration to copper (Cu, [Ar] 3d¹⁰ 4s¹) — the same stabilization effect.
  • Visualize how a fully filled d subshell influences chemical reactivity and oxidation states.
  • Teaching aid for explaining exceptions to the Aufbau principle in atomic structure units.
  • Verify quantum numbers for gold's outermost electrons.
  • Cross-reference with gold element properties for a full physical and chemical picture.

Frequently Asked Questions

Last updated: 2026-06-19 · Reviewed by Nham Vu