Manganese (Mn)

Silvery-gray metal

Manganese is an essential industrial metal used in steel production and is also vital for biological enzyme systems, and with [Ar] 3d⁵ 4s², manganese has seven unpaired electrons giving it a high magnetic moment. It is used in lithium-ion battery cathodes (LiMn₂O₄) and as an oxygen-evolving catalyst in photosynthesis.

Key metrics

Density7.21g/cm³

Melting point1,519K

Boiling point2,334K

Electronegativity1.55Pauling

Discovery

1774discovered

Discovered by: Johan Gottlieb Gahn
Reactivity profile: Oxidizes in air
Reactivity: Medium
Bonding: Metallic

Electron configuration

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

[Ar] 3d5 4s2

Wave function

\Psi_{\text{Mn}} \approx \frac{1}{\sqrt{25!}} \det \left| \chi_1(\mathbf{r}_1) \dots \chi_{25}(\mathbf{r}_{25}) \right|

Probability density $|\Psi|^2$ across the Mn 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: 127 pm
Ionization energy: 717 kJ/mol
Electron affinity: 0 kJ/mol
Crystal structure: Body-centered cubic (bcc)

Oxidation states

+2+4+7

Acid/base

Basic

Strongly acidicStrongly basic

State at 25 °CSolid

1519 K2334 K298 K

Emission spectrum

3 transitions

380450500550600650700780

VioletBlueGreenYellowRed

403.1nmMn I (violet)Violet100%

403.4nmMn IViolet95%

539.8nmMn I (green)Green50%

Dominant line 403.1 nmRange 403–540 nmTransitions 3