Praseodymium (Pr)

Grayish white

Praseodymium creates the deep green color in didymium glass worn by glassblowers, and with three unpaired 4f electrons, praseodymium's absorption bands remove specific wavelengths of light. Praseodymium-doped yttrium aluminum garnet (Nd:YAG alternative) is used in high-power laser systems.

Key metrics

Density6.77g/cm³

Melting point1,208K

Boiling point3,793K

Electronegativity1.13Pauling

Discovery

1885discovered

Discovered by: Carl Auer von Welsbach
Reactivity profile: Oxidizes in air
Reactivity: High
Bonding: Metallic

Electron configuration

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

[Xe] 4f3 6s2

Wave function

\Psi_{\text{Pr}} \approx \frac{1}{\sqrt{59!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{59}(\mathbf{r}_{59}) \right|

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

Crystal structure

Double Hexagonal Close-Packed

Lattice constantsa 1.00 · b 1.00 · c 2.00

Cell anglesα 90° · β 90° · γ 120°

Coordination number12

Atoms per cell4

Atomic packing factor0.74

Physical properties

Atomic radius: 182 pm
Ionization energy: 527 kJ/mol
Electron affinity: 50 kJ/mol
Crystal structure: Double hexagonal close-packed (dhcp)

Oxidation states

Acid/base

Basic

Strongly acidicStrongly basic

State at 25 °CSolid

1208 K3793 K298 K

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

440.9nmPr I (blue)Violet40%

502.3nmPr I (blue-green)Cyan60%

523.4nmPr I (green)Green100%

Dominant line 523.4 nmRange 441–523 nmTransitions 3