NaBa3Si23 crystallizes in the cubic Pm-3n space group. Na(1) is bonded in a 20-coordinate geometry to eight Si(1,1) and twelve Si(2,2,2,2,2) atoms. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 20-coordinate geometry to four Si(3,3,3); eight Si(1,1); and eight Si(2,2,2,2) atoms. In the second Ba site, Ba(1) is bonded in a 20-coordinate geometry to four equivalent Si(3), eight equivalent Si(1), and eight equivalent Si(2) atoms. There are ten inequivalent Si sites. In the first Si site, Si(1) is bonded in a 5-coordinate geometry to one Na(1); three Ba(1,1); one Si(1); and three Si(2,2,2) atoms. In the second Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. In the third Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. In the fourth Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1); two equivalent Ba(1); one Si(2); one Si(3); and two Si(1,1) atoms. In the fifth Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. In the sixth Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. In the seventh Si site, Si(3) is bonded to four Ba(1,1) and four Si(2,2,2) atoms to form a mixture of distorted corner and edge-sharing SiBa4Si4 tetrahedra. In the eighth Si site, Si(3) is bonded to four equivalent Ba(1) and four equivalent Si(2) atoms to form distorted corner-sharing SiBa4Si4 tetrahedra. In the ninth Si site, Si(3) is bonded in a distorted body-centered cubic geometry to four equivalent Ba(1) and four equivalent Si(2) atoms. In the tenth Si site, Si(1) is bonded in a 5-coordinate geometry to one Na(1); three Ba(1,1); one Si(1); and three Si(2,2,2) atoms.
NaBa3Si23 crystallizes in the cubic Pm-3n space group. Na(1) is bonded in a 20-coordinate geometry to eight Si(1,1) and twelve Si(2,2,2,2,2) atoms. All Na(1)-Si(1,1) bond lengths are 3.29 Å. All Na(1)-Si(2,2,2,2,2) bond lengths are 3.38 Å. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 20-coordinate geometry to four Si(3,3,3); eight Si(1,1); and eight Si(2,2,2,2) atoms. All Ba(1)-Si(3,3,3) bond lengths are 3.65 Å. All Ba(1)-Si(1,1) bond lengths are 3.84 Å. All Ba(1)-Si(2,2,2,2) bond lengths are 3.51 Å. In the second Ba site, Ba(1) is bonded in a 20-coordinate geometry to four equivalent Si(3), eight equivalent Si(1), and eight equivalent Si(2) atoms. All Ba(1)-Si(3) bond lengths are 3.65 Å. All Ba(1)-Si(1) bond lengths are 3.84 Å. All Ba(1)-Si(2) bond lengths are 3.51 Å. There are ten inequivalent Si sites. In the first Si site, Si(1) is bonded in a 5-coordinate geometry to one Na(1); three Ba(1,1); one Si(1); and three Si(2,2,2) atoms. The Si(1)-Ba(1) bond length is 3.84 Å. The Si(1)-Si(1) bond length is 2.36 Å. All Si(1)-Si(2,2,2) bond lengths are 2.36 Å. In the second Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. The Si(2)-Si(2) bond length is 2.49 Å. The Si(2)-Si(3) bond length is 2.42 Å. In the third Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. The Si(2)-Si(2) bond length is 2.49 Å. The Si(2)-Si(3) bond length is 2.42 Å. Both Si(2)-Si(1) bond lengths are 2.36 Å. In the fourth Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1); two equivalent Ba(1); one Si(2); one Si(3); and two Si(1,1) atoms. The Si(2)-Si(2) bond length is 2.49 Å. The Si(2)-Si(3) bond length is 2.42 Å. The Si(2)-Si(1) bond length is 2.36 Å. In the fifth Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. The Si(2)-Si(2) bond length is 2.49 Å. The Si(2)-Si(3) bond length is 2.42 Å. Both Si(2)-Si(1) bond lengths are 2.36 Å. In the sixth Si site, Si(2) is bonded in a 7-coordinate geometry to one Na(1), two equivalent Ba(1), one Si(2), one Si(3), and two equivalent Si(1) atoms. The Si(2)-Si(3) bond length is 2.42 Å. In the seventh Si site, Si(3) is bonded to four Ba(1,1) and four Si(2,2,2) atoms to form a mixture of distorted corner and edge-sharing SiBa4Si4 tetrahedra. In the eighth Si site, Si(3) is bonded to four equivalent Ba(1) and four equivalent Si(2) atoms to form distorted corner-sharing SiBa4Si4 tetrahedra. In the ninth Si site, Si(3) is bonded in a distorted body-centered cubic geometry to four equivalent Ba(1) and four equivalent Si(2) atoms. In the tenth Si site, Si(1) is bonded in a 5-coordinate geometry to one Na(1); three Ba(1,1); one Si(1); and three Si(2,2,2) atoms. The Si(1)-Si(1) bond length is 2.36 Å.