Ba12FeSi3S20 crystallizes in the monoclinic Pm space group. There are eight inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one S(1), one S(12), one S(13), one S(14), one S(16), one S(4), one S(5), one S(7), and one S(9) atom. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one S(10), one S(11), one S(13), one S(14), one S(2), one S(3), one S(6), and one S(8) atom. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to one S(10), one S(11), one S(15), one S(16), one S(2), one S(3), one S(5), and one S(7) atom. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one S(1), one S(12), one S(15), one S(16), one S(4), one S(6), one S(8), and one S(9) atom. In the fifth Ba site, Ba(5) is bonded in a 8-coordinate geometry to one S(1), one S(2), one S(6), one S(9), two equivalent S(13), and two equivalent S(15) atoms. In the sixth Ba site, Ba(6) is bonded in a 8-coordinate geometry to one S(1), one S(10), one S(2), one S(5), two equivalent S(14), and two equivalent S(16) atoms. In the seventh Ba site, Ba(7) is bonded in a 8-coordinate geometry to one S(11), one S(3), one S(4), one S(8), two equivalent S(13), and two equivalent S(15) atoms. In the eighth Ba site, Ba(8) is bonded in a 8-coordinate geometry to one S(12), one S(3), one S(4), one S(7), two equivalent S(14), and two equivalent S(16) atoms. Fe(1) is bonded in a tetrahedral geometry to one S(5), one S(9), and two equivalent S(16) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one S(10), one S(6), and two equivalent S(15) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one S(11), one S(7), and two equivalent S(14) atoms. In the third Si site, Si(3) is bonded in a tetrahedral geometry to one S(12), one S(8), and two equivalent S(13) atoms. There are sixteen inequivalent S sites. In the first S site, S(1) is bonded to one Ba(5), one Ba(6), two equivalent Ba(1), and two equivalent Ba(4) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 29-46°. In the second S site, S(2) is bonded to one Ba(5), one Ba(6), two equivalent Ba(2), and two equivalent Ba(3) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 31-46°. In the third S site, S(3) is bonded to one Ba(7), one Ba(8), two equivalent Ba(2), and two equivalent Ba(3) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 31-43°. In the fourth S site, S(4) is bonded to one Ba(7), one Ba(8), two equivalent Ba(1), and two equivalent Ba(4) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 29-43°. In the fifth S site, S(5) is bonded in a 6-coordinate geometry to one Ba(6), two equivalent Ba(1), two equivalent Ba(3), and one Fe(1) atom. In the sixth S site, S(6) is bonded in a 6-coordinate geometry to one Ba(5), two equivalent Ba(2), two equivalent Ba(4), and one Si(1) atom. In the seventh S site, S(7) is bonded in a distorted single-bond geometry to one Ba(8), two equivalent Ba(1), two equivalent Ba(3), and one Si(2) atom. In the eighth S site, S(8) is bonded in a 6-coordinate geometry to one Ba(7), two equivalent Ba(2), two equivalent Ba(4), and one Si(3) atom. In the ninth S site, S(9) is bonded in a 6-coordinate geometry to one Ba(5), two equivalent Ba(1), two equivalent Ba(4), and one Fe(1) atom. In the tenth S site, S(10) is bonded in a 6-coordinate geometry to one Ba(6), two equivalent Ba(2), two equivalent Ba(3), and one Si(1) atom. In the eleventh S site, S(11) is bonded in a 6-coordinate geometry to one Ba(7), two equivalent Ba(2), two equivalent Ba(3), and one Si(2) atom. In the twelfth S site, S(12) is bonded in a 6-coordinate geometry to one Ba(8), two equivalent Ba(1), two equivalent Ba(4), and one Si(3) atom. In the thirteenth S site, S(13) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(2), one Ba(5), one Ba(7), and one Si(3) atom. In the fourteenth S site, S(14) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(2), one Ba(6), one Ba(8), and one Si(2) atom. In the fifteenth S site, S(15) is bonded in a 1-coordinate geometry to one Ba(3), one Ba(4), one Ba(5), one Ba(7), and one Si(1) atom. In the sixteenth S site, S(16) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), one Ba(6), one Ba(8), and one Fe(1) atom.
Ba12FeSi3S20 crystallizes in the monoclinic Pm space group. There are eight inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 8-coordinate geometry to one S(1), one S(12), one S(13), one S(14), one S(16), one S(4), one S(5), one S(7), and one S(9) atom. The Ba(1)-S(1) bond length is 3.41 Å. The Ba(1)-S(12) bond length is 3.31 Å. The Ba(1)-S(13) bond length is 3.34 Å. The Ba(1)-S(14) bond length is 3.56 Å. The Ba(1)-S(16) bond length is 3.74 Å. The Ba(1)-S(4) bond length is 3.27 Å. The Ba(1)-S(5) bond length is 3.42 Å. The Ba(1)-S(7) bond length is 3.27 Å. The Ba(1)-S(9) bond length is 3.36 Å. In the second Ba site, Ba(2) is bonded in a 8-coordinate geometry to one S(10), one S(11), one S(13), one S(14), one S(2), one S(3), one S(6), and one S(8) atom. The Ba(2)-S(10) bond length is 3.43 Å. The Ba(2)-S(11) bond length is 3.28 Å. The Ba(2)-S(13) bond length is 3.57 Å. The Ba(2)-S(14) bond length is 3.29 Å. The Ba(2)-S(2) bond length is 3.45 Å. The Ba(2)-S(3) bond length is 3.26 Å. The Ba(2)-S(6) bond length is 3.39 Å. The Ba(2)-S(8) bond length is 3.25 Å. In the third Ba site, Ba(3) is bonded in a 8-coordinate geometry to one S(10), one S(11), one S(15), one S(16), one S(2), one S(3), one S(5), and one S(7) atom. The Ba(3)-S(10) bond length is 3.29 Å. The Ba(3)-S(11) bond length is 3.44 Å. The Ba(3)-S(15) bond length is 3.33 Å. The Ba(3)-S(16) bond length is 3.44 Å. The Ba(3)-S(2) bond length is 3.29 Å. The Ba(3)-S(3) bond length is 3.37 Å. The Ba(3)-S(5) bond length is 3.25 Å. The Ba(3)-S(7) bond length is 3.36 Å. In the fourth Ba site, Ba(4) is bonded in a 8-coordinate geometry to one S(1), one S(12), one S(15), one S(16), one S(4), one S(6), one S(8), and one S(9) atom. The Ba(4)-S(1) bond length is 3.31 Å. The Ba(4)-S(12) bond length is 3.44 Å. The Ba(4)-S(15) bond length is 3.59 Å. The Ba(4)-S(16) bond length is 3.28 Å. The Ba(4)-S(4) bond length is 3.37 Å. The Ba(4)-S(6) bond length is 3.30 Å. The Ba(4)-S(8) bond length is 3.40 Å. The Ba(4)-S(9) bond length is 3.32 Å. In the fifth Ba site, Ba(5) is bonded in a 8-coordinate geometry to one S(1), one S(2), one S(6), one S(9), two equivalent S(13), and two equivalent S(15) atoms. The Ba(5)-S(1) bond length is 3.52 Å. The Ba(5)-S(2) bond length is 3.18 Å. The Ba(5)-S(6) bond length is 3.26 Å. The Ba(5)-S(9) bond length is 3.24 Å. Both Ba(5)-S(13) bond lengths are 3.13 Å. Both Ba(5)-S(15) bond lengths are 3.25 Å. In the sixth Ba site, Ba(6) is bonded in a 8-coordinate geometry to one S(1), one S(10), one S(2), one S(5), two equivalent S(14), and two equivalent S(16) atoms. The Ba(6)-S(1) bond length is 3.08 Å. The Ba(6)-S(10) bond length is 3.28 Å. The Ba(6)-S(2) bond length is 3.59 Å. The Ba(6)-S(5) bond length is 3.25 Å. Both Ba(6)-S(14) bond lengths are 3.16 Å. Both Ba(6)-S(16) bond lengths are 3.26 Å. In the seventh Ba site, Ba(7) is bonded in a 8-coordinate geometry to one S(11), one S(3), one S(4), one S(8), two equivalent S(13), and two equivalent S(15) atoms. The Ba(7)-S(11) bond length is 3.36 Å. The Ba(7)-S(3) bond length is 3.48 Å. The Ba(7)-S(4) bond length is 3.10 Å. The Ba(7)-S(8) bond length is 3.24 Å. Both Ba(7)-S(13) bond lengths are 3.26 Å. Both Ba(7)-S(15) bond lengths are 3.13 Å. In the eighth Ba site, Ba(8) is bonded in a 8-coordinate geometry to one S(12), one S(3), one S(4), one S(7), two equivalent S(14), and two equivalent S(16) atoms. The Ba(8)-S(12) bond length is 3.31 Å. The Ba(8)-S(3) bond length is 3.12 Å. The Ba(8)-S(4) bond length is 3.61 Å. The Ba(8)-S(7) bond length is 3.27 Å. Both Ba(8)-S(14) bond lengths are 3.25 Å. Both Ba(8)-S(16) bond lengths are 3.07 Å. Fe(1) is bonded in a tetrahedral geometry to one S(5), one S(9), and two equivalent S(16) atoms. The Fe(1)-S(5) bond length is 2.17 Å. The Fe(1)-S(9) bond length is 2.22 Å. Both Fe(1)-S(16) bond lengths are 2.19 Å. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one S(10), one S(6), and two equivalent S(15) atoms. The Si(1)-S(10) bond length is 2.14 Å. The Si(1)-S(6) bond length is 2.12 Å. Both Si(1)-S(15) bond lengths are 2.11 Å. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one S(11), one S(7), and two equivalent S(14) atoms. The Si(2)-S(11) bond length is 2.14 Å. The Si(2)-S(7) bond length is 2.11 Å. Both Si(2)-S(14) bond lengths are 2.12 Å. In the third Si site, Si(3) is bonded in a tetrahedral geometry to one S(12), one S(8), and two equivalent S(13) atoms. The Si(3)-S(12) bond length is 2.14 Å. The Si(3)-S(8) bond length is 2.12 Å. Both Si(3)-S(13) bond lengths are 2.12 Å. There are sixteen inequivalent S sites. In the first S site, S(1) is bonded to one Ba(5), one Ba(6), two equivalent Ba(1), and two equivalent Ba(4) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 29-46°. In the second S site, S(2) is bonded to one Ba(5), one Ba(6), two equivalent Ba(2), and two equivalent Ba(3) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 31-46°. In the third S site, S(3) is bonded to one Ba(7), one Ba(8), two equivalent Ba(2), and two equivalent Ba(3) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 31-43°. In the fourth S site, S(4) is bonded to one Ba(7), one Ba(8), two equivalent Ba(1), and two equivalent Ba(4) atoms to form distorted corner-sharing SBa6 octahedra. The corner-sharing octahedral tilt angles range from 29-43°. In the fifth S site, S(5) is bonded in a 6-coordinate geometry to one Ba(6), two equivalent Ba(1), two equivalent Ba(3), and one Fe(1) atom. In the sixth S site, S(6) is bonded in a 6-coordinate geometry to one Ba(5), two equivalent Ba(2), two equivalent Ba(4), and one Si(1) atom. In the seventh S site, S(7) is bonded in a distorted single-bond geometry to one Ba(8), two equivalent Ba(1), two equivalent Ba(3), and one Si(2) atom. In the eighth S site, S(8) is bonded in a 6-coordinate geometry to one Ba(7), two equivalent Ba(2), two equivalent Ba(4), and one Si(3) atom. In the ninth S site, S(9) is bonded in a 6-coordinate geometry to one Ba(5), two equivalent Ba(1), two equivalent Ba(4), and one Fe(1) atom. In the tenth S site, S(10) is bonded in a 6-coordinate geometry to one Ba(6), two equivalent Ba(2), two equivalent Ba(3), and one Si(1) atom. In the eleventh S site, S(11) is bonded in a 6-coordinate geometry to one Ba(7), two equivalent Ba(2), two equivalent Ba(3), and one Si(2) atom. In the twelfth S site, S(12) is bonded in a 6-coordinate geometry to one Ba(8), two equivalent Ba(1), two equivalent Ba(4), and one Si(3) atom. In the thirteenth S site, S(13) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(2), one Ba(5), one Ba(7), and one Si(3) atom. In the fourteenth S site, S(14) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(2), one Ba(6), one Ba(8), and one Si(2) atom. In the fifteenth S site, S(15) is bonded in a 1-coordinate geometry to one Ba(3), one Ba(4), one Ba(5), one Ba(7), and one Si(1) atom. In the sixteenth S site, S(16) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(3), one Ba(4), one Ba(6), one Ba(8), and one Fe(1) atom.