Lithium manganese oxide (spinel) LiMn₂O₄

Unit cell

Lattice constants

a = 8.245 Å, b = 8.245 Å, c = 8.245 Å; α = 90°, β = 90°, γ = 90°

Cell volume

560.5 ų

Atoms in the cell

56 (Li 8, Mn 16, O 32)

Formula units Z

8

Calculated density

4.29 g cm⁻³

Shortest contact

1.956 Å

Coordination

Li

CN 4 at 1.96 Å (4 O)

Mn

CN 6 at 1.97 Å (6 O)

O

CN 4 at 1.96 Å (1 Li + 3 Mn)

About the structure

• A normal spinel: Li⁺ on the tetrahedral 8a sites, Mn³⁺/Mn⁴⁺ on the octahedral 16d sites, O²⁻ ccp.
• Coordination: Li 4, Mn 6, O 4.
• The empty 16c octahedral sites link the 8a sites into a 3D network, so Li⁺ can move in every direction — unlike the 2D paths of LiCoO₂.
• A low-cost, cobalt-free cathode (LMO); the Mn³⁺ Jahn–Teller distortion limits its cycle life.

Atom positions (fractional, one cell)

Z, coordination numbers, distances, density and packing on this page are computed from these coordinates.