Lithium nitride Li₃N

Unit cell

Lattice constants

a = 3.648 Å, b = 3.648 Å, c = 3.875 Å; α = 90°, β = 90°, γ = 120°

Cell volume

44.7 ų

Atoms in the cell

4 (N 1, Li 3)

Formula units Z

1

Calculated density

1.29 g cm⁻³

Shortest contact

1.938 Å

Coordination

N

CN 8 at 1.94 Å (8 Li)

Li (between layers)

CN 2 at 1.94 Å (2 N)

Li (in layer)

CN 3 at 2.11 Å (3 N)

About the structure

• Li₂N⁻ layers (each N surrounded by 6 Li in the plane) are joined by a single Li⁺ above and below each N, so N is 8-coordinate (hexagonal bipyramid).
• Coordination: N 8, in-layer Li 2 (N–Li 2.11 Å), inter-layer Li 2 (N–Li 1.94 Å).
• One of the best Li⁺ conductors among solids: Li⁺ moves within the Li₂N layers through vacancies.
• The cell shown has γ = 120° (hexagonal).

Atom positions (fractional, one cell)

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