Fig. 1: Schematics of the crystal structures of AMnSb2 (A = Ba, Sr, Ca, Eu, and Yb) and A5MnSb2.
From: High-entropy engineering of the crystal and electronic structures in a Dirac material
a P4/nmm and b I4/mmm aristotype structures of AMnSb2, where ap, bp, and cp represent the lattice vectors of the P4/nmm phase. Black solid lines indicate the unit cells. c Treelike diagram showing space groups assigned for the polymorphs of the AMnSb2 series so far and for the new structure of A5MnSb2. Sb4 layers are depicted, where dashed lines highlight the square shape. The Sb4 layers of Pcmn, I2mm, and P21mn structures involve Sb displacements (illustrated by arrows, whose size represents the displacement magnitude) and Sb–Sb zig-zag chain formation. We chose nonstandard unit cell settings, Pcmn, I2mm, and P21mn (standard setting Pnma, Imm2, and Pmn21 respectively), for the orthorhombic space groups so that the c axes indicate the stacking direction.
