Na4NbZnSi2PO12 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(7), one O(9), and two equivalent O(5) atoms. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(6), one O(8), and one O(9) atom. In the third Na site, Na(3) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(4), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. In the fourth Na site, Na(4) is bonded in a distorted hexagonal planar geometry to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom. Nb(1) is bonded to one O(10), one O(11), one O(12), one O(4), one O(5), and one O(6) atom to form NbO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. Zn(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form distorted ZnO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(2), one O(5), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-39°. In the second Si site, Si(2) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-38°. P(1) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-38°. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Zn(1), and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Na(3), one Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one Zn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Na(2), one Na(3), one Nb(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Na(1), one Nb(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Na(2), one Na(3), one Nb(1), and one P(1) atom. In the seventh O site, O(7) is bonded to one Na(1), one Na(3), one Na(4), one Zn(1), and one Si(2) atom to form distorted face-sharing ONa3ZnSi trigonal bipyramids. In the eighth O site, O(8) is bonded to one Na(2), one Na(3), one Na(4), one Zn(1), and one Si(1) atom to form distorted face-sharing ONa3ZnSi trigonal bipyramids. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(4), one Zn(1), and one P(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Nb(1), and one P(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(4), one Nb(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to one Na(2), one Na(3), one Na(4), one Nb(1), and one Si(2) atom.
Na4NbZnSi2PO12 crystallizes in the monoclinic Cc space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to one O(1), one O(10), one O(11), one O(3), one O(7), one O(9), and two equivalent O(5) atoms. The Na(1)-O(1) bond length is 2.53 Å. The Na(1)-O(10) bond length is 2.80 Å. The Na(1)-O(11) bond length is 2.55 Å. The Na(1)-O(3) bond length is 3.02 Å. The Na(1)-O(7) bond length is 2.40 Å. The Na(1)-O(9) bond length is 2.40 Å. There is one shorter (2.85 Å) and one longer (2.97 Å) Na(1)-O(5) bond length. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(3), one O(4), one O(6), one O(8), and one O(9) atom. The Na(2)-O(11) bond length is 2.71 Å. The Na(2)-O(12) bond length is 2.57 Å. The Na(2)-O(3) bond length is 2.38 Å. The Na(2)-O(4) bond length is 2.98 Å. The Na(2)-O(6) bond length is 2.94 Å. The Na(2)-O(8) bond length is 2.33 Å. The Na(2)-O(9) bond length is 2.51 Å. In the third Na site, Na(3) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(4), one O(6), one O(7), one O(8), and two equivalent O(2) atoms. The Na(3)-O(10) bond length is 2.59 Å. The Na(3)-O(12) bond length is 2.69 Å. The Na(3)-O(4) bond length is 2.90 Å. The Na(3)-O(6) bond length is 3.02 Å. The Na(3)-O(7) bond length is 2.40 Å. The Na(3)-O(8) bond length is 2.46 Å. There is one shorter (2.41 Å) and one longer (2.95 Å) Na(3)-O(2) bond length. In the fourth Na site, Na(4) is bonded in a distorted hexagonal planar geometry to one O(10), one O(11), one O(12), one O(7), one O(8), and one O(9) atom. The Na(4)-O(10) bond length is 2.72 Å. The Na(4)-O(11) bond length is 2.66 Å. The Na(4)-O(12) bond length is 2.64 Å. The Na(4)-O(7) bond length is 2.38 Å. The Na(4)-O(8) bond length is 2.38 Å. The Na(4)-O(9) bond length is 2.57 Å. Nb(1) is bonded to one O(10), one O(11), one O(12), one O(4), one O(5), and one O(6) atom to form NbO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. The Nb(1)-O(10) bond length is 2.11 Å. The Nb(1)-O(11) bond length is 2.05 Å. The Nb(1)-O(12) bond length is 2.05 Å. The Nb(1)-O(4) bond length is 1.95 Å. The Nb(1)-O(5) bond length is 1.97 Å. The Nb(1)-O(6) bond length is 2.04 Å. Zn(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form distorted ZnO6 octahedra that share corners with two equivalent Si(1)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra, and corners with two equivalent P(1)O4 tetrahedra. The Zn(1)-O(1) bond length is 2.11 Å. The Zn(1)-O(2) bond length is 1.96 Å. The Zn(1)-O(3) bond length is 1.98 Å. The Zn(1)-O(7) bond length is 2.16 Å. The Zn(1)-O(8) bond length is 2.13 Å. The Zn(1)-O(9) bond length is 2.35 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(11), one O(2), one O(5), and one O(8) atom to form SiO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-39°. The Si(1)-O(11) bond length is 1.68 Å. The Si(1)-O(2) bond length is 1.60 Å. The Si(1)-O(5) bond length is 1.71 Å. The Si(1)-O(8) bond length is 1.61 Å. In the second Si site, Si(2) is bonded to one O(12), one O(3), one O(4), and one O(7) atom to form SiO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-38°. The Si(2)-O(12) bond length is 1.69 Å. The Si(2)-O(3) bond length is 1.59 Å. The Si(2)-O(4) bond length is 1.71 Å. The Si(2)-O(7) bond length is 1.61 Å. P(1) is bonded to one O(1), one O(10), one O(6), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Zn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-38°. The P(1)-O(1) bond length is 1.52 Å. The P(1)-O(10) bond length is 1.59 Å. The P(1)-O(6) bond length is 1.60 Å. The P(1)-O(9) bond length is 1.52 Å. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Zn(1), and one P(1) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Na(3), one Zn(1), and one Si(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Na(2), one Zn(1), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Na(2), one Na(3), one Nb(1), and one Si(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to two equivalent Na(1), one Nb(1), and one Si(1) atom. In the sixth O site, O(6) is bonded in a distorted bent 150 degrees geometry to one Na(2), one Na(3), one Nb(1), and one P(1) atom. In the seventh O site, O(7) is bonded to one Na(1), one Na(3), one Na(4), one Zn(1), and one Si(2) atom to form distorted face-sharing ONa3ZnSi trigonal bipyramids. In the eighth O site, O(8) is bonded to one Na(2), one Na(3), one Na(4), one Zn(1), and one Si(1) atom to form distorted face-sharing ONa3ZnSi trigonal bipyramids. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Na(1), one Na(2), one Na(4), one Zn(1), and one P(1) atom. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Na(1), one Na(3), one Na(4), one Nb(1), and one P(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(4), one Nb(1), and one Si(1) atom. In the twelfth O site, O(12) is bonded in a 5-coordinate geometry to one Na(2), one Na(3), one Na(4), one Nb(1), and one Si(2) atom.