Na3Cr(Mo3O16)2 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted octahedral geometry to two equivalent O(10), two equivalent O(8), and two equivalent O(9) atoms. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(10), one O(13), one O(15), two equivalent O(11), and two equivalent O(16) atoms. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(8), and one O(9) atom. In the second Mo site, Mo(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(2), one O(3), one O(5), and one O(6) atom. In the third Mo site, Mo(3) is bonded in a 5-coordinate geometry to one O(1), one O(12), one O(4), one O(6), and one O(7) atom. Cr(1) is bonded in an octahedral geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mo(1), one Mo(3), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mo(1), one Mo(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Mo(2) and one Cr(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Mo(1) and one Mo(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Mo(1) and one Mo(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Mo(2) and one Mo(3) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Mo(3) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Na(1) and one Mo(1) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Na(1) and one Mo(1) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), and one Mo(2) atom. In the eleventh O site, O(11) is bonded in a distorted T-shaped geometry to two equivalent Na(2) and one Mo(2) atom. In the twelfth O site, O(12) is bonded in a single-bond geometry to one Mo(3) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one Na(2) and one O(14) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one O(13) atom. In the fifteenth O site, O(15) is bonded in a single-bond geometry to one Na(2) atom. In the sixteenth O site, O(16) is bonded in a 3-coordinate geometry to two equivalent Na(2) and one O(16) atom.
Na3Cr(Mo3O16)2 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted octahedral geometry to two equivalent O(10), two equivalent O(8), and two equivalent O(9) atoms. Both Na(1)-O(10) bond lengths are 2.45 Å. Both Na(1)-O(8) bond lengths are 2.50 Å. Both Na(1)-O(9) bond lengths are 2.70 Å. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(10), one O(13), one O(15), two equivalent O(11), and two equivalent O(16) atoms. The Na(2)-O(10) bond length is 3.00 Å. The Na(2)-O(13) bond length is 2.73 Å. The Na(2)-O(15) bond length is 2.33 Å. There is one shorter (2.25 Å) and one longer (2.35 Å) Na(2)-O(11) bond length. There is one shorter (2.72 Å) and one longer (2.82 Å) Na(2)-O(16) bond length. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), one O(5), one O(8), and one O(9) atom. The Mo(1)-O(1) bond length is 2.38 Å. The Mo(1)-O(2) bond length is 2.41 Å. The Mo(1)-O(4) bond length is 1.95 Å. The Mo(1)-O(5) bond length is 1.94 Å. The Mo(1)-O(8) bond length is 1.74 Å. The Mo(1)-O(9) bond length is 1.73 Å. In the second Mo site, Mo(2) is bonded in a 6-coordinate geometry to one O(10), one O(11), one O(2), one O(3), one O(5), and one O(6) atom. The Mo(2)-O(10) bond length is 1.74 Å. The Mo(2)-O(11) bond length is 1.77 Å. The Mo(2)-O(2) bond length is 2.13 Å. The Mo(2)-O(3) bond length is 2.49 Å. The Mo(2)-O(5) bond length is 1.99 Å. The Mo(2)-O(6) bond length is 1.90 Å. In the third Mo site, Mo(3) is bonded in a 5-coordinate geometry to one O(1), one O(12), one O(4), one O(6), and one O(7) atom. The Mo(3)-O(1) bond length is 2.18 Å. The Mo(3)-O(12) bond length is 1.75 Å. The Mo(3)-O(4) bond length is 1.98 Å. The Mo(3)-O(6) bond length is 1.95 Å. The Mo(3)-O(7) bond length is 1.71 Å. Cr(1) is bonded in an octahedral geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Both Cr(1)-O(1) bond lengths are 1.98 Å. Both Cr(1)-O(2) bond lengths are 1.96 Å. Both Cr(1)-O(3) bond lengths are 1.75 Å. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mo(1), one Mo(3), and one Cr(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Mo(1), one Mo(2), and one Cr(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Mo(2) and one Cr(1) atom. In the fourth O site, O(4) is bonded in a bent 120 degrees geometry to one Mo(1) and one Mo(3) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Mo(1) and one Mo(2) atom. In the sixth O site, O(6) is bonded in a bent 120 degrees geometry to one Mo(2) and one Mo(3) atom. In the seventh O site, O(7) is bonded in a single-bond geometry to one Mo(3) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Na(1) and one Mo(1) atom. In the ninth O site, O(9) is bonded in a distorted single-bond geometry to one Na(1) and one Mo(1) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Na(1), one Na(2), and one Mo(2) atom. In the eleventh O site, O(11) is bonded in a distorted T-shaped geometry to two equivalent Na(2) and one Mo(2) atom. In the twelfth O site, O(12) is bonded in a single-bond geometry to one Mo(3) atom. In the thirteenth O site, O(13) is bonded in a bent 120 degrees geometry to one Na(2) and one O(14) atom. The O(13)-O(14) bond length is 1.23 Å. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one O(13) atom. In the fifteenth O site, O(15) is bonded in a single-bond geometry to one Na(2) atom. In the sixteenth O site, O(16) is bonded in a 3-coordinate geometry to two equivalent Na(2) and one O(16) atom. The O(16)-O(16) bond length is 1.24 Å.