Tantalum (Ta)

Blue-gray metal

Tantalum is a dense, corrosion-resistant metal used in surgical implants and the tiny capacitors inside your phone, and with [Xe] 4f¹⁴ 5d³ 6s², tantalum forms a stable Ta₂O₅ oxide layer that is an excellent dielectric. Its biocompatibility means it integrates with bone without rejection, and its capacitors enable smartphone miniaturization.

Key metrics

Density16.65g/cm³

Melting point3,290K

Boiling point5,731K

Electronegativity1.5Pauling

Discovery

1802discovered

Discovered by: Anders Gustaf Ekeberg
Reactivity profile: Highly corrosion resistant
Reactivity: Low
Bonding: Metallic

Electron configuration

\textcolor{#6b7280}{[Xe]}\; \textcolor{#a855f7}{4_{f}^{14}}\; \textcolor{#22c55e}{5_{d}^{3}}\; \textcolor{#ef4444}{6_{s}^{2}}

[Xe] 4f14 5d3 6s2

Wave function

\Psi_{\text{Ta}} \approx \frac{1}{\sqrt{73!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{73}(\mathbf{r}_{73}) \right|

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

Crystal structure

Body-Centered Cubic

Lattice constantsa = 1.00

Cell anglesα = β = γ = 90°

Coordination number8

Atoms per cell2

Atomic packing factor0.68

Physical properties

Atomic radius: 146 pm
Ionization energy: 761 kJ/mol
Electron affinity: 31 kJ/mol
Crystal structure: Body-centered cubic (bcc)

Oxidation states

Acid/base

Basic

Strongly acidicStrongly basic

State at 25 °CSolid

3290 K5731 K298 K

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

409.1nmTa I (violet)Violet60%

471.3nmTa I (blue)Blue100%

530.5nmTa I (green)Green40%

Dominant line 471.3 nmRange 409–531 nmTransitions 3