Ba4AuSi22 crystallizes in the orthorhombic Ama2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 20-coordinate geometry to one Si(10), one Si(11), one Si(12), one Si(7), two equivalent Si(1), two equivalent Si(2), two equivalent Si(3), two equivalent Si(4), two equivalent Si(5), two equivalent Si(6), two equivalent Si(8), and two equivalent Si(9) atoms. In the second Ba site, Ba(2) is bonded in a 16-coordinate geometry to one Au(1), one Si(14), two equivalent Si(13), two equivalent Si(5), two equivalent Si(6), two equivalent Si(8), two equivalent Si(9), and four equivalent Si(1) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to two equivalent Au(1), two equivalent Si(1), two equivalent Si(10), two equivalent Si(11), two equivalent Si(12), two equivalent Si(14), and two equivalent Si(7) atoms. In the fourth Ba site, Ba(4) is bonded in a 9-coordinate geometry to one Au(1), one Si(14), two equivalent Si(5), two equivalent Si(6), two equivalent Si(8), and two equivalent Si(9) atoms. Au(1) is bonded to one Ba(2), one Ba(4), two equivalent Ba(3), one Si(11), one Si(7), and two equivalent Si(5) atoms to form AuBa4Si4 tetrahedra that share corners with two equivalent Au(1)Ba4Si4 tetrahedra and corners with two equivalent Si(13)Ba2Si4 tetrahedra. There are fourteen inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Si(1), one Si(5), one Si(6), and one Si(7) atom. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to one Ba(1), one Si(10), one Si(2), one Si(8), and one Si(9) atom. In the third Si site, Si(3) is bonded in a 5-coordinate geometry to one Ba(1), one Si(11), one Si(4), one Si(6), and one Si(8) atom. In the fourth Si site, Si(4) is bonded in a 5-coordinate geometry to one Ba(1), one Si(12), one Si(3), one Si(5), and one Si(9) atom. In the fifth Si site, Si(5) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(4), one Au(1), one Si(1), one Si(4), and one Si(8) atom. In the sixth Si site, Si(6) is bonded in a 7-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Si(1), one Si(13), one Si(3), and one Si(6) atom. In the seventh Si site, Si(7) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(3), one Au(1), one Si(12), and two equivalent Si(1) atoms. In the eighth Si site, Si(8) is bonded in a 7-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Si(14), one Si(2), one Si(3), and one Si(5) atom. In the ninth Si site, Si(9) is bonded in a 7-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Si(13), one Si(2), one Si(4), and one Si(9) atom. In the tenth Si site, Si(10) is bonded in a 7-coordinate geometry to one Ba(1), two equivalent Ba(3), one Si(11), one Si(14), and two equivalent Si(2) atoms. In the eleventh Si site, Si(11) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(3), one Au(1), one Si(10), and two equivalent Si(3) atoms. In the twelfth Si site, Si(12) is bonded in a 7-coordinate geometry to one Ba(1), two equivalent Ba(3), one Si(14), one Si(7), and two equivalent Si(4) atoms. In the thirteenth Si site, Si(13) is bonded to two equivalent Ba(2), two equivalent Si(6), and two equivalent Si(9) atoms to form distorted SiBa2Si4 tetrahedra that share corners with two equivalent Au(1)Ba4Si4 tetrahedra and corners with two equivalent Si(13)Ba2Si4 tetrahedra. In the fourteenth Si site, Si(14) is bonded in a 8-coordinate geometry to one Ba(2), one Ba(4), two equivalent Ba(3), one Si(10), one Si(12), and two equivalent Si(8) atoms.
Ba4AuSi22 crystallizes in the orthorhombic Ama2 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 20-coordinate geometry to one Si(10), one Si(11), one Si(12), one Si(7), two equivalent Si(1), two equivalent Si(2), two equivalent Si(3), two equivalent Si(4), two equivalent Si(5), two equivalent Si(6), two equivalent Si(8), and two equivalent Si(9) atoms. The Ba(1)-Si(10) bond length is 3.45 Å. The Ba(1)-Si(11) bond length is 3.39 Å. The Ba(1)-Si(12) bond length is 3.39 Å. The Ba(1)-Si(7) bond length is 3.35 Å. Both Ba(1)-Si(1) bond lengths are 3.31 Å. Both Ba(1)-Si(2) bond lengths are 3.38 Å. Both Ba(1)-Si(3) bond lengths are 3.34 Å. Both Ba(1)-Si(4) bond lengths are 3.36 Å. Both Ba(1)-Si(5) bond lengths are 3.42 Å. Both Ba(1)-Si(6) bond lengths are 3.43 Å. Both Ba(1)-Si(8) bond lengths are 3.45 Å. Both Ba(1)-Si(9) bond lengths are 3.48 Å. In the second Ba site, Ba(2) is bonded in a 16-coordinate geometry to one Au(1), one Si(14), two equivalent Si(13), two equivalent Si(5), two equivalent Si(6), two equivalent Si(8), two equivalent Si(9), and four equivalent Si(1) atoms. The Ba(2)-Au(1) bond length is 3.56 Å. The Ba(2)-Si(14) bond length is 3.69 Å. Both Ba(2)-Si(13) bond lengths are 3.75 Å. Both Ba(2)-Si(5) bond lengths are 3.45 Å. Both Ba(2)-Si(6) bond lengths are 3.56 Å. Both Ba(2)-Si(8) bond lengths are 3.54 Å. Both Ba(2)-Si(9) bond lengths are 3.63 Å. There are two shorter (3.80 Å) and two longer (3.82 Å) Ba(2)-Si(1) bond lengths. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to two equivalent Au(1), two equivalent Si(1), two equivalent Si(10), two equivalent Si(11), two equivalent Si(12), two equivalent Si(14), and two equivalent Si(7) atoms. Both Ba(3)-Au(1) bond lengths are 3.62 Å. Both Ba(3)-Si(1) bond lengths are 3.74 Å. Both Ba(3)-Si(10) bond lengths are 3.65 Å. Both Ba(3)-Si(11) bond lengths are 3.58 Å. Both Ba(3)-Si(12) bond lengths are 3.55 Å. Both Ba(3)-Si(14) bond lengths are 3.78 Å. Both Ba(3)-Si(7) bond lengths are 3.47 Å. In the fourth Ba site, Ba(4) is bonded in a 9-coordinate geometry to one Au(1), one Si(14), two equivalent Si(5), two equivalent Si(6), two equivalent Si(8), and two equivalent Si(9) atoms. The Ba(4)-Au(1) bond length is 3.59 Å. The Ba(4)-Si(14) bond length is 3.73 Å. Both Ba(4)-Si(5) bond lengths are 3.45 Å. Both Ba(4)-Si(6) bond lengths are 3.51 Å. Both Ba(4)-Si(8) bond lengths are 3.50 Å. Both Ba(4)-Si(9) bond lengths are 3.59 Å. Au(1) is bonded to one Ba(2), one Ba(4), two equivalent Ba(3), one Si(11), one Si(7), and two equivalent Si(5) atoms to form AuBa4Si4 tetrahedra that share corners with two equivalent Au(1)Ba4Si4 tetrahedra and corners with two equivalent Si(13)Ba2Si4 tetrahedra. The Au(1)-Si(11) bond length is 2.48 Å. The Au(1)-Si(7) bond length is 2.47 Å. Both Au(1)-Si(5) bond lengths are 2.48 Å. There are fourteen inequivalent Si sites. In the first Si site, Si(1) is bonded in a 8-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), one Si(1), one Si(5), one Si(6), and one Si(7) atom. The Si(1)-Si(1) bond length is 2.38 Å. The Si(1)-Si(5) bond length is 2.41 Å. The Si(1)-Si(6) bond length is 2.40 Å. The Si(1)-Si(7) bond length is 2.41 Å. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to one Ba(1), one Si(10), one Si(2), one Si(8), and one Si(9) atom. The Si(2)-Si(10) bond length is 2.41 Å. The Si(2)-Si(2) bond length is 2.34 Å. The Si(2)-Si(8) bond length is 2.40 Å. The Si(2)-Si(9) bond length is 2.41 Å. In the third Si site, Si(3) is bonded in a 5-coordinate geometry to one Ba(1), one Si(11), one Si(4), one Si(6), and one Si(8) atom. The Si(3)-Si(11) bond length is 2.41 Å. The Si(3)-Si(4) bond length is 2.36 Å. The Si(3)-Si(6) bond length is 2.40 Å. The Si(3)-Si(8) bond length is 2.41 Å. In the fourth Si site, Si(4) is bonded in a 5-coordinate geometry to one Ba(1), one Si(12), one Si(3), one Si(5), and one Si(9) atom. The Si(4)-Si(12) bond length is 2.42 Å. The Si(4)-Si(5) bond length is 2.40 Å. The Si(4)-Si(9) bond length is 2.41 Å. In the fifth Si site, Si(5) is bonded in a distorted single-bond geometry to one Ba(1), one Ba(2), one Ba(4), one Au(1), one Si(1), one Si(4), and one Si(8) atom. The Si(5)-Si(8) bond length is 2.47 Å. In the sixth Si site, Si(6) is bonded in a 7-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Si(1), one Si(13), one Si(3), and one Si(6) atom. The Si(6)-Si(13) bond length is 2.40 Å. The Si(6)-Si(6) bond length is 2.57 Å. In the seventh Si site, Si(7) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(3), one Au(1), one Si(12), and two equivalent Si(1) atoms. The Si(7)-Si(12) bond length is 2.50 Å. In the eighth Si site, Si(8) is bonded in a 7-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Si(14), one Si(2), one Si(3), and one Si(5) atom. The Si(8)-Si(14) bond length is 2.45 Å. In the ninth Si site, Si(9) is bonded in a 7-coordinate geometry to one Ba(1), one Ba(2), one Ba(4), one Si(13), one Si(2), one Si(4), and one Si(9) atom. The Si(9)-Si(13) bond length is 2.43 Å. The Si(9)-Si(9) bond length is 2.48 Å. In the tenth Si site, Si(10) is bonded in a 7-coordinate geometry to one Ba(1), two equivalent Ba(3), one Si(11), one Si(14), and two equivalent Si(2) atoms. The Si(10)-Si(11) bond length is 2.47 Å. The Si(10)-Si(14) bond length is 2.46 Å. In the eleventh Si site, Si(11) is bonded in a distorted single-bond geometry to one Ba(1), two equivalent Ba(3), one Au(1), one Si(10), and two equivalent Si(3) atoms. In the twelfth Si site, Si(12) is bonded in a 7-coordinate geometry to one Ba(1), two equivalent Ba(3), one Si(14), one Si(7), and two equivalent Si(4) atoms. The Si(12)-Si(14) bond length is 2.44 Å. In the thirteenth Si site, Si(13) is bonded to two equivalent Ba(2), two equivalent Si(6), and two equivalent Si(9) atoms to form distorted SiBa2Si4 tetrahedra that share corners with two equivalent Au(1)Ba4Si4 tetrahedra and corners with two equivalent Si(13)Ba2Si4 tetrahedra. In the fourteenth Si site, Si(14) is bonded in a 8-coordinate geometry to one Ba(2), one Ba(4), two equivalent Ba(3), one Si(10), one Si(12), and two equivalent Si(8) atoms.