Thallium Electron Configuration
Orbital diagram
- Valence electrons
- 3
- Unpaired electrons
- 1
- Block
- p-block
- Magnetism (atom)
- paramagnetic
Electrons per shell
| K (n = 1) | 2 |
|---|---|
| L (n = 2) | 8 |
| M (n = 3) | 18 |
| N (n = 4) | 32 |
| O (n = 5) | 18 |
| P (n = 6) | 3 |
Thallium ion configurations
| Ion | Electrons | Configuration |
|---|---|---|
| Tl+ | 80 | [Xe] 4f14 5d10 6s2 |
| Tl3+ | 78 | [Xe] 4f14 5d10 |
How to write it
Place 81 electrons into subshells in the Aufbau order (1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p), filling s with 2, p with 6, d with 10 and f with 14. Thallium sits in period 6, group 13, in the p-block, so its last electron enters a p subshell. Replacing the inner electrons with the previous noble gas gives the shorthand [Xe] 4f14 5d10 6s2 6p1.
Try thallium and its ions in the calculator, or see the full thallium data sheet.
Thallium electron configuration FAQ
What is the electron configuration of thallium?
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 5s² 5p⁶ 4f¹⁴ 5d¹⁰ 6s² 6p¹. Shorthand (noble gas) notation: [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹.
What is the noble gas configuration of thallium?
[Xe] 4f¹⁴ 5d¹⁰ 6s² 6p¹. The bracket stands for the Xe core electrons.
How many valence electrons does thallium have?
3 (outer shell (n = 6)).
How many unpaired electrons does thallium have?
1 in the ground state, following Hund’s rule. An atom with unpaired electrons is paramagnetic.
What is the electron configuration of Tl+?
[Xe] 4f¹⁴ 5d¹⁰ 6s² (80 electrons).
What is the electron configuration of Tl3+?
[Xe] 4f¹⁴ 5d¹⁰ (78 electrons).