Palladium Electron Configuration
Palladium (Pd, Z=46) has the unique electron configuration [Kr] 4d¹⁰ — a completely filled d subshell with an empty 5s orbital, making it the only 4d transition metal with a d¹⁰ s⁰ ground state.
Use the Palladium Electron Configuration
Palladium — Electron Configuration
Atomic number 46 · Transition metal · Period 5, Group 10 · d-block
Aufbau Exception: d¹⁰ s⁰
The Aufbau principle predicts [Kr] 4d⁸ 5s² for palladium. The actual ground state is [Kr] 4d¹⁰ — both predicted 5s electrons shift into 4d, leaving the 5s completely empty. Palladium is the only 4d transition metal with this d¹⁰ s⁰ ground state.
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 |
| 5s | s orbital, shell n=5 (empty — anomalous) | 0 | 2 | 5s⁰ |
| Total | 46 | |||
Full Configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰
All subshells written explicitly. Note: 5s⁰ is omitted.
Noble-Gas Shorthand
[Kr] 4d¹⁰
[Kr] = 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶.
Aufbau Prediction (wrong)
[Kr] 4d⁸ 5s²
Aufbau fills 5s before 4d, but d¹⁰ is more stable.
Shell Fill Summary
Shell 5 is completely empty in palladium's ground state — the anomalous d¹⁰ configuration leaves 5s unoccupied. The next element, silver (Z=47), adds one electron into 5s: [Kr] 4d¹⁰ 5s¹.
Group 10 Configurations: Ni, Pd, Pt
| Element | Z | Actual Configuration | Anomaly? |
|---|---|---|---|
| Nickel (Ni) | 28 | [Ar] 3d⁸ 4s² | No (follows Aufbau) |
| Palladium (Pd) | 46 | [Kr] 4d¹⁰ | Yes — d¹⁰ s⁰, unique |
| Platinum (Pt) | 78 | [Xe] 4f¹⁴ 5d⁹ 6s¹ | Yes — one 6s electron, d⁹ s¹ |
Palladium is the only Group 10 element — and the only 4d transition metal overall — that completely empties its outermost s orbital in the ground state.
Summary
Palladium (Pd) is atomic number 46, a Period 5 transition metal in Group 10. Its ground-state electron configuration is 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ — written in noble-gas shorthand as [Kr] 4d¹⁰. This is the only transition metal in the 4d series that adopts a d¹⁰ s⁰ configuration: the 5s orbital is completely empty while the 4d subshell is completely filled. This tool presents the full subshell table, an orbital box diagram, quantum numbers for all 46 electrons, and context for palladium's key properties.
How it works
- The Aufbau principle predicts [Kr] 4d⁸ 5s² for palladium — 8 electrons in 4d and 2 in 5s.
- Instead, both 5s electrons shift into 4d, yielding [Kr] 4d¹⁰ with a completely filled d subshell and an empty 5s.
- A fully filled d subshell (10 electrons across five orbitals) achieves maximum exchange-energy stabilization.
- The energy gain from maximizing electron pairing in 4d outweighs the cost of vacating 5s.
- Palladium is unique among 4d metals: it is the only one in this series with a d¹⁰ s⁰ ground state.
- Nickel (Z=28) shows a related trend one period above but retains two 4s electrons rather than fully emptying them.
Use cases
- Verify palladium's actual ground-state configuration vs. the Aufbau prediction.
- Understand why [Kr] 4d¹⁰ is uniquely stable compared with [Kr] 4d⁸ 5s².
- Study the d¹⁰ s⁰ anomaly and compare it with other anomalous transition metals.
- Review palladium's oxidation states (+2, +4) and how d¹⁰ relates to Pd chemistry.
- Use the quantum-number table for all 46 electrons in exam preparation.
- Teaching aid for inorganic chemistry courses on d-block electronic structure exceptions.
- Quick reference for periodic trends across Period 5 transition metals.
- Compare Pd with Pt (Period 6) and Ni (Period 4) in the same Group 10.