Ca11Bi10 crystallizes in the monoclinic C2/m space group. There are seven inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one Bi(1), one Bi(2), one Bi(5), two equivalent Bi(6), and two equivalent Bi(7) atoms to form a mixture of distorted face, corner, and edge-sharing CaBi7 pentagonal bipyramids. In the second Ca site, Ca(2) is bonded to one Bi(1), one Bi(2), one Bi(5), two equivalent Bi(7), and two equivalent Bi(8) atoms to form a mixture of distorted face, corner, and edge-sharing CaBi7 pentagonal bipyramids. In the third Ca site, Ca(3) is bonded in a 7-coordinate geometry to one Bi(3), one Bi(6), one Bi(8), two equivalent Bi(1), and two equivalent Bi(2) atoms. In the fourth Ca site, Ca(4) is bonded in a 7-coordinate geometry to one Bi(4), two equivalent Bi(1), two equivalent Bi(2), and two equivalent Bi(7) atoms. In the fifth Ca site, Ca(5) is bonded in a 9-coordinate geometry to one Bi(2), one Bi(6), one Bi(8), two equivalent Bi(3), two equivalent Bi(4), and two equivalent Bi(7) atoms. In the sixth Ca site, Ca(6) is bonded in a 7-coordinate geometry to one Bi(3), one Bi(4), one Bi(5), one Bi(6), one Bi(7), and two equivalent Bi(1) atoms. In the seventh Ca site, Ca(7) is bonded in a 7-coordinate geometry to one Bi(3), one Bi(4), one Bi(5), one Bi(7), one Bi(8), and two equivalent Bi(1) atoms. There are eight inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 8-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), one Ca(4), two equivalent Ca(6), and two equivalent Ca(7) atoms. In the second Bi site, Bi(2) is bonded in a 9-coordinate geometry to one Ca(5), two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(3), and two equivalent Ca(4) atoms. In the third Bi site, Bi(3) is bonded in a 11-coordinate geometry to one Ca(3), two equivalent Ca(5), two equivalent Ca(6), two equivalent Ca(7), one Bi(6), one Bi(8), and two equivalent Bi(4) atoms. In the fourth Bi site, Bi(4) is bonded in a 11-coordinate geometry to one Ca(4), two equivalent Ca(5), two equivalent Ca(6), two equivalent Ca(7), two equivalent Bi(3), and two equivalent Bi(7) atoms. In the fifth Bi site, Bi(5) is bonded in a 8-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(6), and two equivalent Ca(7) atoms. In the sixth Bi site, Bi(6) is bonded in a 10-coordinate geometry to one Ca(3), one Ca(5), two equivalent Ca(6), four equivalent Ca(1), one Bi(3), and one Bi(6) atom. In the seventh Bi site, Bi(7) is bonded in a 10-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), one Ca(7), two equivalent Ca(1), two equivalent Ca(2), one Bi(4), and one Bi(7) atom. In the eighth Bi site, Bi(8) is bonded in a 10-coordinate geometry to one Ca(3), one Ca(5), two equivalent Ca(7), four equivalent Ca(2), one Bi(3), and one Bi(8) atom.
Ca11Bi10 crystallizes in the monoclinic C2/m space group. There are seven inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one Bi(1), one Bi(2), one Bi(5), two equivalent Bi(6), and two equivalent Bi(7) atoms to form a mixture of distorted face, corner, and edge-sharing CaBi7 pentagonal bipyramids. The Ca(1)-Bi(1) bond length is 3.59 Å. The Ca(1)-Bi(2) bond length is 3.28 Å. The Ca(1)-Bi(5) bond length is 3.25 Å. There is one shorter (3.55 Å) and one longer (3.70 Å) Ca(1)-Bi(6) bond length. There is one shorter (3.55 Å) and one longer (3.70 Å) Ca(1)-Bi(7) bond length. In the second Ca site, Ca(2) is bonded to one Bi(1), one Bi(2), one Bi(5), two equivalent Bi(7), and two equivalent Bi(8) atoms to form a mixture of distorted face, corner, and edge-sharing CaBi7 pentagonal bipyramids. The Ca(2)-Bi(1) bond length is 3.58 Å. The Ca(2)-Bi(2) bond length is 3.28 Å. The Ca(2)-Bi(5) bond length is 3.25 Å. There is one shorter (3.55 Å) and one longer (3.70 Å) Ca(2)-Bi(7) bond length. There is one shorter (3.55 Å) and one longer (3.70 Å) Ca(2)-Bi(8) bond length. In the third Ca site, Ca(3) is bonded in a 7-coordinate geometry to one Bi(3), one Bi(6), one Bi(8), two equivalent Bi(1), and two equivalent Bi(2) atoms. The Ca(3)-Bi(3) bond length is 3.62 Å. The Ca(3)-Bi(6) bond length is 3.85 Å. The Ca(3)-Bi(8) bond length is 3.86 Å. Both Ca(3)-Bi(1) bond lengths are 3.03 Å. There is one shorter (3.63 Å) and one longer (3.64 Å) Ca(3)-Bi(2) bond length. In the fourth Ca site, Ca(4) is bonded in a 7-coordinate geometry to one Bi(4), two equivalent Bi(1), two equivalent Bi(2), and two equivalent Bi(7) atoms. The Ca(4)-Bi(4) bond length is 3.63 Å. Both Ca(4)-Bi(1) bond lengths are 3.03 Å. Both Ca(4)-Bi(2) bond lengths are 3.63 Å. Both Ca(4)-Bi(7) bond lengths are 3.86 Å. In the fifth Ca site, Ca(5) is bonded in a 9-coordinate geometry to one Bi(2), one Bi(6), one Bi(8), two equivalent Bi(3), two equivalent Bi(4), and two equivalent Bi(7) atoms. The Ca(5)-Bi(2) bond length is 3.68 Å. The Ca(5)-Bi(6) bond length is 3.57 Å. The Ca(5)-Bi(8) bond length is 3.57 Å. There is one shorter (3.69 Å) and one longer (3.72 Å) Ca(5)-Bi(3) bond length. Both Ca(5)-Bi(4) bond lengths are 3.70 Å. Both Ca(5)-Bi(7) bond lengths are 3.57 Å. In the sixth Ca site, Ca(6) is bonded in a 7-coordinate geometry to one Bi(3), one Bi(4), one Bi(5), one Bi(6), one Bi(7), and two equivalent Bi(1) atoms. The Ca(6)-Bi(3) bond length is 3.56 Å. The Ca(6)-Bi(4) bond length is 3.58 Å. The Ca(6)-Bi(5) bond length is 3.26 Å. The Ca(6)-Bi(6) bond length is 3.28 Å. The Ca(6)-Bi(7) bond length is 3.28 Å. There is one shorter (3.27 Å) and one longer (3.28 Å) Ca(6)-Bi(1) bond length. In the seventh Ca site, Ca(7) is bonded in a 7-coordinate geometry to one Bi(3), one Bi(4), one Bi(5), one Bi(7), one Bi(8), and two equivalent Bi(1) atoms. The Ca(7)-Bi(3) bond length is 3.58 Å. The Ca(7)-Bi(4) bond length is 3.57 Å. The Ca(7)-Bi(5) bond length is 3.26 Å. The Ca(7)-Bi(7) bond length is 3.28 Å. The Ca(7)-Bi(8) bond length is 3.28 Å. Both Ca(7)-Bi(1) bond lengths are 3.28 Å. There are eight inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 8-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), one Ca(4), two equivalent Ca(6), and two equivalent Ca(7) atoms. In the second Bi site, Bi(2) is bonded in a 9-coordinate geometry to one Ca(5), two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(3), and two equivalent Ca(4) atoms. In the third Bi site, Bi(3) is bonded in a 11-coordinate geometry to one Ca(3), two equivalent Ca(5), two equivalent Ca(6), two equivalent Ca(7), one Bi(6), one Bi(8), and two equivalent Bi(4) atoms. The Bi(3)-Bi(6) bond length is 3.32 Å. The Bi(3)-Bi(8) bond length is 3.35 Å. Both Bi(3)-Bi(4) bond lengths are 3.21 Å. In the fourth Bi site, Bi(4) is bonded in a 11-coordinate geometry to one Ca(4), two equivalent Ca(5), two equivalent Ca(6), two equivalent Ca(7), two equivalent Bi(3), and two equivalent Bi(7) atoms. Both Bi(4)-Bi(7) bond lengths are 3.33 Å. In the fifth Bi site, Bi(5) is bonded in a 8-coordinate geometry to two equivalent Ca(1), two equivalent Ca(2), two equivalent Ca(6), and two equivalent Ca(7) atoms. In the sixth Bi site, Bi(6) is bonded in a 10-coordinate geometry to one Ca(3), one Ca(5), two equivalent Ca(6), four equivalent Ca(1), one Bi(3), and one Bi(6) atom. The Bi(6)-Bi(6) bond length is 3.17 Å. In the seventh Bi site, Bi(7) is bonded in a 10-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), one Ca(7), two equivalent Ca(1), two equivalent Ca(2), one Bi(4), and one Bi(7) atom. The Bi(7)-Bi(7) bond length is 3.17 Å. In the eighth Bi site, Bi(8) is bonded in a 10-coordinate geometry to one Ca(3), one Ca(5), two equivalent Ca(7), four equivalent Ca(2), one Bi(3), and one Bi(8) atom. The Bi(8)-Bi(8) bond length is 3.16 Å.