Scandium (Sc)

Silvery-white metal

Scandium is a soft, silvery Transition often used in aluminum alloys to improve strength and corrosion resistance, and as the first d-block element with [Ar] 3d¹ 4s², scandium has a very high melting point (1814 K) and forms Sc₂O₃, which is used in high-intensity discharge lamps for stadiums.

Key metrics

Density2.99g/cm³

Melting point1,814K

Boiling point3,109K

Electronegativity1.36Pauling

Discovery

1879discovered

Discovered by: Lars Fredrik Nilson
Reactivity profile: Reacts slowly with air
Reactivity: Medium
Bonding: Metallic

Electron configuration

\textcolor{#6b7280}{[Ar]}\; \textcolor{#22c55e}{3_{d}^{1}}\; \textcolor{#ef4444}{4_{s}^{2}}

[Ar] 3d1 4s2

Wave function

\Psi_{\text{Sc}} \approx \frac{1}{\sqrt{21!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{21}(\mathbf{r}_{21}) \right|

Probability density $|\Psi|^2$ across the Sc 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: 162 pm
Ionization energy: 633 kJ/mol
Electron affinity: 18 kJ/mol
Crystal structure: Hexagonal close-packed (hcp)

Oxidation states

Acid/base

Basic

Strongly acidicStrongly basic

State at 25 °CSolid

1814 K3109 K298 K

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

402.0nmSc IViolet90%

402.4nmSc I (violet)Violet100%

535.1nmSc I (green)Green60%

Dominant line 402.4 nmRange 402–535 nmTransitions 3