The series RE₅Li₂Sn₇ (RE = Ce, Pr, Nd, Sm) revisited: crystal structure of RE₅Li_2−xSn_7+x [0 ≤ x ≤ 0.03 (1)]

Polar inter­metallic phases with complex structures are reported in the RE–Li–Sn system (RE = Ce, Pr, Nd, Sm). They crystallize in the chiral ortho­rhom­bic space group P2₁2₁2₁ (No. 19), which is relatively uncommon among inter­metallic phases.