Lawrencium (Lr)

Unknown

Lawrencium is the final actinide element, bridging the gap between the actinides and the transition metals, and with the anomalous [Rn] 5f¹⁴ 7s² 7p¹ configuration (electron in 7p instead of expected 6d), lawrencium-266 (half-life 11 hours) is the most stable superheavy actinide. Its chemistry is still being explored.

Key metrics

Density14.4g/cm³predicted

Melting point1,900Kpredicted

Boiling point1,030Kpredicted

Electronegativity1.3Paulingpredicted

Discovery

1961discovered

Discovered by: Lawrence Berkeley Lab
Reactivity profile: Extremely radioactive
Reactivity: High
Bonding: Metallic

Electron configuration

\textcolor{#6b7280}{[Rn]}\; \textcolor{#a855f7}{5_{f}^{14}}\; \textcolor{#ef4444}{7_{s}^{2}}\; \textcolor{#3b82f6}{7_{p}^{1}}

[Rn] 5f14 7s2 7p1

Wave function

\Psi_{\text{Lr}} \approx \frac{1}{\sqrt{103!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{103}(\mathbf{r}_{103}) \right|

Probability density $|\Psi|^2$ across the Lr valence shell.

Crystal structure

Hexagonal Close-Packed

Lattice constantsa 1.00 · b 1.00 · c 1.63

Cell anglesα 90° · β 90° · γ 120°

Coordination number12

Atoms per cell2

Atomic packing factor0.74

Physical properties

Atomic radius: 191 pmpredicted
Ionization energy: 470 kJ/molpredicted
Electron affinity: 0 kJ/molpredicted
Crystal structure: Hexagonal close-packed (predicted)

Oxidation statespredicted

Acid/base

Basic

Strongly acidicStrongly basic

State at 25 °CSolid

1900 K1030 K298 K

predicted

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

420.0nmLr I (blue)Violet60%

465.0nmLr IBlue40%

480.0nmLr I (blue-green)Blue100%

Dominant line 480.0 nmRange 420–480 nmTransitions 3