Na3ScTiSi(PO6)2 crystallizes in the monoclinic Cc space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(2), one O(5), and one O(6) atom. In the second Na site, Na(2) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(7), one O(8), and one O(9) atom. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(11), one O(2), one O(5), one O(6), and one O(7) atom. Sc(1) is bonded to one O(1), one O(11), one O(4), one O(5), one O(8), and one O(9) atom to form ScO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. Ti(1) is bonded to one O(10), one O(12), one O(2), one O(3), one O(6), and one O(7) atom to form TiO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. Si(1) is bonded to one O(1), one O(10), one O(6), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra and corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-41°. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(12), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra and corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 20-43°. In the second P site, P(2) is bonded to one O(2), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra and corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-40°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(2), one Sc(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Ti(1), and one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Sc(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(3), one Sc(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal pyramidal geometry to one Na(1), one Na(3), one Ti(1), and one Si(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(2), one Na(3), one Ti(1), and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Na(2), one Sc(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(2), one Sc(1), and one P(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(2), one Ti(1), and one Si(1) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Sc(1), and one P(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ti(1), and one P(1) atom.
Na3ScTiSi(PO6)2 crystallizes in the monoclinic Cc space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(11), one O(12), one O(2), one O(5), and one O(6) atom. The Na(1)-O(1) bond length is 2.35 Å. The Na(1)-O(11) bond length is 2.70 Å. The Na(1)-O(12) bond length is 2.33 Å. The Na(1)-O(2) bond length is 2.56 Å. The Na(1)-O(5) bond length is 2.55 Å. The Na(1)-O(6) bond length is 2.40 Å. In the second Na site, Na(2) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(7), one O(8), and one O(9) atom. The Na(2)-O(1) bond length is 2.39 Å. The Na(2)-O(10) bond length is 2.57 Å. The Na(2)-O(11) bond length is 2.57 Å. The Na(2)-O(12) bond length is 2.67 Å. The Na(2)-O(2) bond length is 2.38 Å. The Na(2)-O(7) bond length is 2.91 Å. The Na(2)-O(8) bond length is 2.97 Å. The Na(2)-O(9) bond length is 2.57 Å. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to one O(11), one O(2), one O(5), one O(6), and one O(7) atom. The Na(3)-O(11) bond length is 2.47 Å. The Na(3)-O(2) bond length is 2.73 Å. The Na(3)-O(5) bond length is 2.38 Å. The Na(3)-O(6) bond length is 2.42 Å. The Na(3)-O(7) bond length is 2.45 Å. Sc(1) is bonded to one O(1), one O(11), one O(4), one O(5), one O(8), and one O(9) atom to form ScO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Sc(1)-O(1) bond length is 2.06 Å. The Sc(1)-O(11) bond length is 2.18 Å. The Sc(1)-O(4) bond length is 2.12 Å. The Sc(1)-O(5) bond length is 2.15 Å. The Sc(1)-O(8) bond length is 1.92 Å. The Sc(1)-O(9) bond length is 2.10 Å. Ti(1) is bonded to one O(10), one O(12), one O(2), one O(3), one O(6), and one O(7) atom to form TiO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The Ti(1)-O(10) bond length is 1.91 Å. The Ti(1)-O(12) bond length is 2.04 Å. The Ti(1)-O(2) bond length is 2.15 Å. The Ti(1)-O(3) bond length is 1.91 Å. The Ti(1)-O(6) bond length is 1.98 Å. The Ti(1)-O(7) bond length is 2.06 Å. Si(1) is bonded to one O(1), one O(10), one O(6), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra and corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-41°. The Si(1)-O(1) bond length is 1.62 Å. The Si(1)-O(10) bond length is 1.69 Å. The Si(1)-O(6) bond length is 1.65 Å. The Si(1)-O(8) bond length is 1.61 Å. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(12), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra and corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 20-43°. The P(1)-O(11) bond length is 1.54 Å. The P(1)-O(12) bond length is 1.55 Å. The P(1)-O(3) bond length is 1.58 Å. The P(1)-O(4) bond length is 1.52 Å. In the second P site, P(2) is bonded to one O(2), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra and corners with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 24-40°. The P(2)-O(2) bond length is 1.57 Å. The P(2)-O(5) bond length is 1.54 Å. The P(2)-O(7) bond length is 1.58 Å. The P(2)-O(9) bond length is 1.53 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(2), one Sc(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Ti(1), and one P(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ti(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Sc(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(3), one Sc(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal pyramidal geometry to one Na(1), one Na(3), one Ti(1), and one Si(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Na(2), one Na(3), one Ti(1), and one P(2) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to one Na(2), one Sc(1), and one Si(1) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Na(2), one Sc(1), and one P(2) atom. In the tenth O site, O(10) is bonded in a 3-coordinate geometry to one Na(2), one Ti(1), and one Si(1) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(3), one Sc(1), and one P(1) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Na(1), one Na(2), one Ti(1), and one P(1) atom.