Chevrel phase (lead molybdenum sulfide) PbMo₆S₈

Unit cell

Lattice constants

a = 9.198 Å, b = 9.198 Å, c = 11.442 Å; α = 90°, β = 90°, γ = 120°

Cell volume

838.3 ų

Atoms in the cell

45 (S 24, Pb 3, Mo 18)

Formula units Z

3

Calculated density

4.95 g cm⁻³

Shortest contact

2.383 Å

Coordination

S

CN 4 at 2.38 Å (3.75 Mo)

Pb

CN 8 at 2.78 Å (8 S)

Mo

CN 5 at 2.38 Å (5 S)

About the structure

• Mo₆S₈ clusters — an octahedron of Mo atoms inside a cube of S atoms — stack along the rhombohedral axis with Pb²⁺ in the cavities between clusters.
• Chevrel phases were the first materials to show very high upper critical fields (PbMo₆S₈: ~60 T) and are today the archetype cathode for rechargeable magnesium batteries.
• Coordinates from the Crystallography Open Database, entry 1537987 (open data); hydrogen and water sites with partial occupancy below 0.5 are left out.

Atom positions (fractional, one cell)

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