Materials Data on Ba(MgPb)2 by Materials Project
Ba(MgPb)2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Ba is bonded in a 12-coordinate geometry to eight Mg and eight Pb atoms. There are four shorter (3.82 Å) and four longer (4.03 Å) Ba–Mg bond lengths. There are four shorter (3.85 Å) and four longer (3.97 Å) Ba–Pb bond lengths. There are two inequivalent Mg sites. In the first Mg site, Mg is bonded in a 5-coordinate geometry to four equivalent Ba and five Pb atoms. There are one shorter (2.86 Å) and four longer (3.03 Å) Mg–Pb bond lengths. In the second Mg site, Mg is bonded to four equivalent Ba and four equivalent Pb atoms to form MgBa4Pb4 tetrahedra that share corners with twelve equivalent PbBa4Mg4 tetrahedra, edges with two equivalent PbBa4Mg4 tetrahedra, edges with four equivalent MgBa4Pb4 tetrahedra, and faces with four equivalent MgBa4Pb4 tetrahedra. All Mg–Pb bond lengths are 3.02 Å. There are two inequivalent Pb sites. In the first Pb site, Pb is bonded in a 9-coordinate geometry to four equivalent Ba and five Mg atoms. In the second Pb site, Pb is bonded to four equivalent Ba and four equivalent Mg atoms to form distorted PbBa4Mg4 tetrahedra that share corners with twelve equivalent MgBa4Pb4 tetrahedra, edges with two equivalent MgBa4Pb4 tetrahedra, edges with four equivalent PbBa4Mg4 tetrahedra, and faces with four equivalent PbBa4Mg4 tetrahedra.