CsNa2Be6(BO3)5 crystallizes in the monoclinic C2 space group. Cs(1) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(7) atoms. Na(1) is bonded in a 7-coordinate geometry to one O(4), one O(5), one O(6), one O(8), and three equivalent O(3) atoms. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to one O(1), one O(7), and two equivalent O(2) atoms to form corner-sharing BeO4 tetrahedra. In the second Be site, Be(2) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form corner-sharing BeO4 tetrahedra. In the third Be site, Be(3) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form corner-sharing BeO4 tetrahedra. There are three inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(3), one O(7), and one O(8) atom. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(6) atom. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(4) and two equivalent O(5) atoms. There are eight inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 120 degrees geometry to three equivalent Na(1), one Be(2), and one B(1) atom. In the second O site, O(4) is bonded in a trigonal planar geometry to two equivalent Na(1), two equivalent Be(3), and one B(3) atom. In the third O site, O(5) is bonded in a distorted trigonal planar geometry to one Na(1), one Be(2), one Be(3), and one B(3) atom. In the fourth O site, O(6) is bonded in a trigonal planar geometry to one Na(1), one Be(2), one Be(3), and one B(2) atom. In the fifth O site, O(7) is bonded in a bent 120 degrees geometry to two equivalent Cs(1), one Be(1), and one B(1) atom. In the sixth O site, O(8) is bonded in a distorted T-shaped geometry to one Na(1), one Be(3), and one B(1) atom. In the seventh O site, O(1) is bonded in a distorted trigonal planar geometry to one Cs(1), one Be(1), one Be(2), and one B(2) atom. In the eighth O site, O(2) is bonded in a trigonal planar geometry to two equivalent Be(1) and one B(2) atom.
CsNa2Be6(BO3)5 crystallizes in the monoclinic C2 space group. Cs(1) is bonded in a 6-coordinate geometry to two equivalent O(1) and four equivalent O(7) atoms. Both Cs(1)-O(1) bond lengths are 3.34 Å. There are two shorter (3.25 Å) and two longer (3.26 Å) Cs(1)-O(7) bond lengths. Na(1) is bonded in a 7-coordinate geometry to one O(4), one O(5), one O(6), one O(8), and three equivalent O(3) atoms. The Na(1)-O(4) bond length is 2.75 Å. The Na(1)-O(5) bond length is 2.54 Å. The Na(1)-O(6) bond length is 2.75 Å. The Na(1)-O(8) bond length is 2.35 Å. There are a spread of Na(1)-O(3) bond distances ranging from 2.49-2.53 Å. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to one O(1), one O(7), and two equivalent O(2) atoms to form corner-sharing BeO4 tetrahedra. The Be(1)-O(1) bond length is 1.67 Å. The Be(1)-O(7) bond length is 1.58 Å. There is one shorter (1.63 Å) and one longer (1.68 Å) Be(1)-O(2) bond length. In the second Be site, Be(2) is bonded to one O(1), one O(3), one O(5), and one O(6) atom to form corner-sharing BeO4 tetrahedra. The Be(2)-O(1) bond length is 1.65 Å. The Be(2)-O(3) bond length is 1.62 Å. The Be(2)-O(5) bond length is 1.62 Å. The Be(2)-O(6) bond length is 1.66 Å. In the third Be site, Be(3) is bonded to one O(4), one O(5), one O(6), and one O(8) atom to form corner-sharing BeO4 tetrahedra. The Be(3)-O(4) bond length is 1.69 Å. The Be(3)-O(5) bond length is 1.68 Å. The Be(3)-O(6) bond length is 1.66 Å. The Be(3)-O(8) bond length is 1.53 Å. There are three inequivalent B sites. In the first B site, B(1) is bonded in a trigonal planar geometry to one O(3), one O(7), and one O(8) atom. The B(1)-O(3) bond length is 1.43 Å. The B(1)-O(7) bond length is 1.37 Å. The B(1)-O(8) bond length is 1.36 Å. In the second B site, B(2) is bonded in a trigonal planar geometry to one O(1), one O(2), and one O(6) atom. The B(2)-O(1) bond length is 1.37 Å. The B(2)-O(2) bond length is 1.38 Å. The B(2)-O(6) bond length is 1.38 Å. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(4) and two equivalent O(5) atoms. The B(3)-O(4) bond length is 1.38 Å. Both B(3)-O(5) bond lengths are 1.38 Å. There are eight inequivalent O sites. In the first O site, O(3) is bonded in a distorted bent 120 degrees geometry to three equivalent Na(1), one Be(2), and one B(1) atom. In the second O site, O(4) is bonded in a trigonal planar geometry to two equivalent Na(1), two equivalent Be(3), and one B(3) atom. In the third O site, O(5) is bonded in a distorted trigonal planar geometry to one Na(1), one Be(2), one Be(3), and one B(3) atom. In the fourth O site, O(6) is bonded in a trigonal planar geometry to one Na(1), one Be(2), one Be(3), and one B(2) atom. In the fifth O site, O(7) is bonded in a bent 120 degrees geometry to two equivalent Cs(1), one Be(1), and one B(1) atom. In the sixth O site, O(8) is bonded in a distorted T-shaped geometry to one Na(1), one Be(3), and one B(1) atom. In the seventh O site, O(1) is bonded in a distorted trigonal planar geometry to one Cs(1), one Be(1), one Be(2), and one B(2) atom. In the eighth O site, O(2) is bonded in a trigonal planar geometry to two equivalent Be(1) and one B(2) atom.