Ba(YSe2)2 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one Se(2), two equivalent Se(4), and three equivalent Se(3) atoms to form a mixture of corner and edge-sharing YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-60°. In the second Y site, Y(2) is bonded to one Se(4), two equivalent Se(2), and three equivalent Se(1) atoms to form a mixture of corner and edge-sharing YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-60°. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ba(1) and three equivalent Y(2) atoms to form a mixture of distorted corner and edge-sharing SeBa2Y3 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Y(1), and two equivalent Y(2) atoms. In the third Se site, Se(3) is bonded to two equivalent Ba(1) and three equivalent Y(1) atoms to form a mixture of corner and edge-sharing SeBa2Y3 square pyramids. In the fourth Se site, Se(4) is bonded to two equivalent Ba(1), one Y(2), and two equivalent Y(1) atoms to form a mixture of distorted corner and edge-sharing SeBa2Y3 trigonal bipyramids.
Ba(YSe2)2 crystallizes in the orthorhombic Pnma space group. Ba(1) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. Both Ba(1)-Se(1) bond lengths are 3.35 Å. Both Ba(1)-Se(2) bond lengths are 3.39 Å. Both Ba(1)-Se(3) bond lengths are 3.33 Å. There is one shorter (3.49 Å) and one longer (3.51 Å) Ba(1)-Se(4) bond length. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one Se(2), two equivalent Se(4), and three equivalent Se(3) atoms to form a mixture of corner and edge-sharing YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-60°. The Y(1)-Se(2) bond length is 2.91 Å. Both Y(1)-Se(4) bond lengths are 2.84 Å. There is one shorter (2.86 Å) and two longer (2.89 Å) Y(1)-Se(3) bond lengths. In the second Y site, Y(2) is bonded to one Se(4), two equivalent Se(2), and three equivalent Se(1) atoms to form a mixture of corner and edge-sharing YSe6 octahedra. The corner-sharing octahedral tilt angles range from 48-60°. The Y(2)-Se(4) bond length is 2.88 Å. Both Y(2)-Se(2) bond lengths are 2.90 Å. There is one shorter (2.83 Å) and two longer (2.88 Å) Y(2)-Se(1) bond lengths. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ba(1) and three equivalent Y(2) atoms to form a mixture of distorted corner and edge-sharing SeBa2Y3 trigonal bipyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ba(1), one Y(1), and two equivalent Y(2) atoms. In the third Se site, Se(3) is bonded to two equivalent Ba(1) and three equivalent Y(1) atoms to form a mixture of corner and edge-sharing SeBa2Y3 square pyramids. In the fourth Se site, Se(4) is bonded to two equivalent Ba(1), one Y(2), and two equivalent Y(1) atoms to form a mixture of distorted corner and edge-sharing SeBa2Y3 trigonal bipyramids.