Na2B5H5O12 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 7-coordinate geometry to one O(1), one O(10), one O(12), one O(6), one O(9), and two equivalent O(7) atoms. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one H(5), one O(11), one O(12), one O(4), one O(8), and two equivalent O(2) atoms. There are five inequivalent B sites. In the first B site, B(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing BO4 tetrahedra. In the second B site, B(2) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form corner-sharing BO4 tetrahedra. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. In the fourth B site, B(4) is bonded in a trigonal planar geometry to one O(10), one O(7), and one O(9) atom. In the fifth B site, B(5) is bonded in a trigonal planar geometry to one O(1), one O(10), and one O(8) atom. There are five inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(5) atom. In the third H site, H(3) is bonded in a distorted linear geometry to one O(5) and one O(9) atom. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(11) atom. In the fifth H site, H(5) is bonded in a single-bond geometry to one Na(2) and one O(12) atom. 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 B(1), and one B(5) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Na(2), one B(1), and one H(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one B(1) and one B(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(2), one B(1), and one B(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one B(3), one H(2), and one H(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Na(1), one B(2), and one B(3) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to two equivalent Na(1), one B(2), and one B(4) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Na(2), one B(2), and one B(5) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Na(1), one B(4), and one H(3) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one Na(1), one B(4), and one B(5) atom. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one Na(2) and one H(4) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one H(5) atom.
Na2B5H5O12 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 7-coordinate geometry to one O(1), one O(10), one O(12), one O(6), one O(9), and two equivalent O(7) atoms. The Na(1)-O(1) bond length is 2.41 Å. The Na(1)-O(10) bond length is 2.51 Å. The Na(1)-O(12) bond length is 2.34 Å. The Na(1)-O(6) bond length is 2.78 Å. The Na(1)-O(9) bond length is 2.59 Å. There is one shorter (2.45 Å) and one longer (2.56 Å) Na(1)-O(7) bond length. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one H(5), one O(11), one O(12), one O(4), one O(8), and two equivalent O(2) atoms. The Na(2)-H(5) bond length is 2.52 Å. The Na(2)-O(11) bond length is 2.45 Å. The Na(2)-O(12) bond length is 2.79 Å. The Na(2)-O(4) bond length is 2.29 Å. The Na(2)-O(8) bond length is 2.53 Å. There is one shorter (2.42 Å) and one longer (2.73 Å) Na(2)-O(2) bond length. There are five inequivalent B sites. In the first B site, B(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing BO4 tetrahedra. The B(1)-O(1) bond length is 1.47 Å. The B(1)-O(2) bond length is 1.48 Å. The B(1)-O(3) bond length is 1.47 Å. The B(1)-O(4) bond length is 1.49 Å. In the second B site, B(2) is bonded to one O(3), one O(6), one O(7), and one O(8) atom to form corner-sharing BO4 tetrahedra. The B(2)-O(3) bond length is 1.46 Å. The B(2)-O(6) bond length is 1.50 Å. The B(2)-O(7) bond length is 1.48 Å. The B(2)-O(8) bond length is 1.48 Å. In the third B site, B(3) is bonded in a trigonal planar geometry to one O(4), one O(5), and one O(6) atom. The B(3)-O(4) bond length is 1.36 Å. The B(3)-O(5) bond length is 1.38 Å. The B(3)-O(6) bond length is 1.39 Å. In the fourth B site, B(4) is bonded in a trigonal planar geometry to one O(10), one O(7), and one O(9) atom. The B(4)-O(10) bond length is 1.39 Å. The B(4)-O(7) bond length is 1.37 Å. The B(4)-O(9) bond length is 1.36 Å. In the fifth B site, B(5) is bonded in a trigonal planar geometry to one O(1), one O(10), and one O(8) atom. The B(5)-O(1) bond length is 1.36 Å. The B(5)-O(10) bond length is 1.41 Å. The B(5)-O(8) bond length is 1.37 Å. There are five inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) atom. The H(1)-O(2) bond length is 1.00 Å. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(5) atom. The H(2)-O(5) bond length is 1.00 Å. In the third H site, H(3) is bonded in a distorted linear geometry to one O(5) and one O(9) atom. The H(3)-O(5) bond length is 1.65 Å. The H(3)-O(9) bond length is 1.01 Å. In the fourth H site, H(4) is bonded in a single-bond geometry to one O(11) atom. The H(4)-O(11) bond length is 1.02 Å. In the fifth H site, H(5) is bonded in a single-bond geometry to one Na(2) and one O(12) atom. The H(5)-O(12) bond length is 1.01 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 B(1), and one B(5) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to two equivalent Na(2), one B(1), and one H(1) atom. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one B(1) and one B(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(2), one B(1), and one B(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one B(3), one H(2), and one H(3) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Na(1), one B(2), and one B(3) atom. In the seventh O site, O(7) is bonded in a distorted bent 120 degrees geometry to two equivalent Na(1), one B(2), and one B(4) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Na(2), one B(2), and one B(5) atom. In the ninth O site, O(9) is bonded in a distorted bent 120 degrees geometry to one Na(1), one B(4), and one H(3) atom. In the tenth O site, O(10) is bonded in a distorted bent 120 degrees geometry to one Na(1), one B(4), and one B(5) atom. In the eleventh O site, O(11) is bonded in a distorted single-bond geometry to one Na(2) and one H(4) atom. In the twelfth O site, O(12) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one H(5) atom.