KNaCu(Si2O5)2 crystallizes in the triclinic P-1 space group. K(1) is bonded in a 10-coordinate geometry to one O(10), one O(3), one O(5), one O(7), one O(8), one O(9), two equivalent O(2), and two equivalent O(6) atoms. Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(5), one O(7), one O(8), and two equivalent O(4) atoms. Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(4), one O(5), and one O(7) atom. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(10), one O(2), one O(3), and one O(5) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(6), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(2), one O(7), one O(8), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(10), one O(4), one O(6), and one O(9) atom to form corner-sharing SiO4 tetrahedra. There are ten inequivalent O sites. In the first O site, O(10) is bonded in a 2-coordinate geometry to one K(1), one Na(1), one Si(1), and one Si(4) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Cu(1), and one Si(2) atom. In the third O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Si(1), and one Si(3) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one Si(1), and one Si(2) atom. In the fifth O site, O(4) is bonded to two equivalent Na(1), one Cu(1), and one Si(4) atom to form distorted edge-sharing ONa2CuSi trigonal pyramids. In the sixth O site, O(5) is bonded in a 4-coordinate geometry to one K(1), one Na(1), one Cu(1), and one Si(1) atom. In the seventh O site, O(6) is bonded in a 2-coordinate geometry to two equivalent K(1), one Si(2), and one Si(4) atom. In the eighth O site, O(7) is bonded in a 4-coordinate geometry to one K(1), one Na(1), one Cu(1), and one Si(3) atom. In the ninth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one K(1), one Na(1), one Si(2), and one Si(3) atom. In the tenth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one K(1), one Si(3), and one Si(4) atom.
KNaCu(Si2O5)2 crystallizes in the triclinic P-1 space group. K(1) is bonded in a 10-coordinate geometry to one O(10), one O(3), one O(5), one O(7), one O(8), one O(9), two equivalent O(2), and two equivalent O(6) atoms. The K(1)-O(10) bond length is 2.89 Å. The K(1)-O(3) bond length is 3.01 Å. The K(1)-O(5) bond length is 3.10 Å. The K(1)-O(7) bond length is 2.86 Å. The K(1)-O(8) bond length is 3.42 Å. The K(1)-O(9) bond length is 3.20 Å. There is one shorter (2.78 Å) and one longer (3.34 Å) K(1)-O(2) bond length. There is one shorter (2.71 Å) and one longer (3.13 Å) K(1)-O(6) bond length. Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(5), one O(7), one O(8), and two equivalent O(4) atoms. The Na(1)-O(1) bond length is 2.49 Å. The Na(1)-O(10) bond length is 2.96 Å. The Na(1)-O(5) bond length is 2.58 Å. The Na(1)-O(7) bond length is 2.45 Å. The Na(1)-O(8) bond length is 2.95 Å. There is one shorter (2.41 Å) and one longer (2.57 Å) Na(1)-O(4) bond length. Cu(1) is bonded in a rectangular see-saw-like geometry to one O(1), one O(4), one O(5), and one O(7) atom. The Cu(1)-O(1) bond length is 1.99 Å. The Cu(1)-O(4) bond length is 2.00 Å. The Cu(1)-O(5) bond length is 1.99 Å. The Cu(1)-O(7) bond length is 1.98 Å. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(10), one O(2), one O(3), and one O(5) atom to form corner-sharing SiO4 tetrahedra. The Si(1)-O(10) bond length is 1.65 Å. The Si(1)-O(2) bond length is 1.64 Å. The Si(1)-O(3) bond length is 1.64 Å. The Si(1)-O(5) bond length is 1.60 Å. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(6), and one O(8) atom to form corner-sharing SiO4 tetrahedra. The Si(2)-O(1) bond length is 1.60 Å. The Si(2)-O(3) bond length is 1.65 Å. The Si(2)-O(6) bond length is 1.65 Å. The Si(2)-O(8) bond length is 1.66 Å. In the third Si site, Si(3) is bonded to one O(2), one O(7), one O(8), and one O(9) atom to form corner-sharing SiO4 tetrahedra. The Si(3)-O(2) bond length is 1.65 Å. The Si(3)-O(7) bond length is 1.60 Å. The Si(3)-O(8) bond length is 1.65 Å. The Si(3)-O(9) bond length is 1.64 Å. In the fourth Si site, Si(4) is bonded to one O(10), one O(4), one O(6), and one O(9) atom to form corner-sharing SiO4 tetrahedra. The Si(4)-O(10) bond length is 1.66 Å. The Si(4)-O(4) bond length is 1.60 Å. The Si(4)-O(6) bond length is 1.65 Å. The Si(4)-O(9) bond length is 1.64 Å. There are ten inequivalent O sites. In the first O site, O(10) is bonded in a 2-coordinate geometry to one K(1), one Na(1), one Si(1), and one Si(4) atom. In the second O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Cu(1), and one Si(2) atom. In the third O site, O(2) is bonded in a distorted bent 150 degrees geometry to two equivalent K(1), one Si(1), and one Si(3) atom. In the fourth O site, O(3) is bonded in a distorted bent 150 degrees geometry to one K(1), one Si(1), and one Si(2) atom. In the fifth O site, O(4) is bonded to two equivalent Na(1), one Cu(1), and one Si(4) atom to form distorted edge-sharing ONa2CuSi trigonal pyramids. In the sixth O site, O(5) is bonded in a 4-coordinate geometry to one K(1), one Na(1), one Cu(1), and one Si(1) atom. In the seventh O site, O(6) is bonded in a 2-coordinate geometry to two equivalent K(1), one Si(2), and one Si(4) atom. In the eighth O site, O(7) is bonded in a 4-coordinate geometry to one K(1), one Na(1), one Cu(1), and one Si(3) atom. In the ninth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one K(1), one Na(1), one Si(2), and one Si(3) atom. In the tenth O site, O(9) is bonded in a distorted bent 150 degrees geometry to one K(1), one Si(3), and one Si(4) atom.