Sr4Bi11 crystallizes in the triclinic P-1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one Bi(1), one Bi(3), one Bi(4), one Bi(6), two equivalent Bi(2), and two equivalent Bi(5) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Bi(4), one Bi(5), one Bi(6), two equivalent Bi(1), and two equivalent Bi(3) atoms. There are six inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 7-coordinate geometry to one Sr(1), two equivalent Sr(2), one Bi(1), one Bi(2), one Bi(3), and one Bi(4) atom. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), one Bi(1), one Bi(4), one Bi(5), and one Bi(6) atom. In the third Bi site, Bi(3) is bonded in a 3-coordinate geometry to one Sr(1), two equivalent Sr(2), and one Bi(1) atom. In the fourth Bi site, Bi(4) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(2), one Bi(1), and one Bi(2) atom. In the fifth Bi site, Bi(5) is bonded in a 1-coordinate geometry to one Sr(2), two equivalent Sr(1), and one Bi(2) atom. In the sixth Bi site, Bi(6) is bonded in a 4-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Bi(2) atoms.
Sr4Bi11 crystallizes in the triclinic P-1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to one Bi(1), one Bi(3), one Bi(4), one Bi(6), two equivalent Bi(2), and two equivalent Bi(5) atoms. The Sr(1)-Bi(1) bond length is 3.46 Å. The Sr(1)-Bi(3) bond length is 3.37 Å. The Sr(1)-Bi(4) bond length is 3.35 Å. The Sr(1)-Bi(6) bond length is 3.59 Å. There is one shorter (3.53 Å) and one longer (3.67 Å) Sr(1)-Bi(2) bond length. There is one shorter (3.77 Å) and one longer (3.80 Å) Sr(1)-Bi(5) bond length. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one Bi(4), one Bi(5), one Bi(6), two equivalent Bi(1), and two equivalent Bi(3) atoms. The Sr(2)-Bi(4) bond length is 3.87 Å. The Sr(2)-Bi(5) bond length is 3.46 Å. The Sr(2)-Bi(6) bond length is 3.51 Å. There is one shorter (3.61 Å) and one longer (3.83 Å) Sr(2)-Bi(1) bond length. There is one shorter (3.62 Å) and one longer (3.81 Å) Sr(2)-Bi(3) bond length. There are six inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 7-coordinate geometry to one Sr(1), two equivalent Sr(2), one Bi(1), one Bi(2), one Bi(3), and one Bi(4) atom. The Bi(1)-Bi(1) bond length is 3.53 Å. The Bi(1)-Bi(2) bond length is 3.36 Å. The Bi(1)-Bi(3) bond length is 3.19 Å. The Bi(1)-Bi(4) bond length is 3.12 Å. In the second Bi site, Bi(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), one Bi(1), one Bi(4), one Bi(5), and one Bi(6) atom. The Bi(2)-Bi(4) bond length is 3.47 Å. The Bi(2)-Bi(5) bond length is 3.12 Å. The Bi(2)-Bi(6) bond length is 3.48 Å. In the third Bi site, Bi(3) is bonded in a 3-coordinate geometry to one Sr(1), two equivalent Sr(2), and one Bi(1) atom. In the fourth Bi site, Bi(4) is bonded in a distorted single-bond geometry to one Sr(1), one Sr(2), one Bi(1), and one Bi(2) atom. In the fifth Bi site, Bi(5) is bonded in a 1-coordinate geometry to one Sr(2), two equivalent Sr(1), and one Bi(2) atom. In the sixth Bi site, Bi(6) is bonded in a 4-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Bi(2) atoms.