NaBH4 crystallizes in the monoclinic Pm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one H(4), two equivalent H(1), two equivalent H(2), and two equivalent H(5) atoms. In the second Na site, Na(2) is bonded in a 9-coordinate geometry to one H(4), two equivalent H(1), two equivalent H(2), two equivalent H(3), and two equivalent H(6) atoms. There are two inequivalent B sites. In the first B site, B(1) is bonded in a tetrahedral geometry to one H(3), one H(4), and two equivalent H(2) atoms. In the second B site, B(2) is bonded in a tetrahedral geometry to one H(5), one H(6), and two equivalent H(1) atoms. There are six inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one B(2) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one B(1) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to two equivalent Na(2) and one B(1) atom. In the fourth H site, H(4) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one B(1) atom. In the fifth H site, H(5) is bonded in a distorted single-bond geometry to two equivalent Na(1) and one B(2) atom. In the sixth H site, H(6) is bonded in a distorted single-bond geometry to two equivalent Na(2) and one B(2) atom.
NaBH4 crystallizes in the monoclinic Pm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one H(4), two equivalent H(1), two equivalent H(2), and two equivalent H(5) atoms. The Na(1)-H(4) bond length is 2.49 Å. Both Na(1)-H(1) bond lengths are 2.26 Å. Both Na(1)-H(2) bond lengths are 2.36 Å. Both Na(1)-H(5) bond lengths are 2.41 Å. In the second Na site, Na(2) is bonded in a 9-coordinate geometry to one H(4), two equivalent H(1), two equivalent H(2), two equivalent H(3), and two equivalent H(6) atoms. The Na(2)-H(4) bond length is 2.42 Å. Both Na(2)-H(1) bond lengths are 2.41 Å. Both Na(2)-H(2) bond lengths are 2.54 Å. There is one shorter (2.28 Å) and one longer (2.40 Å) Na(2)-H(3) bond length. Both Na(2)-H(6) bond lengths are 2.53 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a tetrahedral geometry to one H(3), one H(4), and two equivalent H(2) atoms. The B(1)-H(3) bond length is 1.22 Å. The B(1)-H(4) bond length is 1.23 Å. Both B(1)-H(2) bond lengths are 1.23 Å. In the second B site, B(2) is bonded in a tetrahedral geometry to one H(5), one H(6), and two equivalent H(1) atoms. The B(2)-H(5) bond length is 1.23 Å. The B(2)-H(6) bond length is 1.23 Å. Both B(2)-H(1) bond lengths are 1.23 Å. There are six inequivalent H sites. In the first H site, H(1) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one B(2) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one B(1) atom. In the third H site, H(3) is bonded in a distorted single-bond geometry to two equivalent Na(2) and one B(1) atom. In the fourth H site, H(4) is bonded in a distorted single-bond geometry to one Na(1), one Na(2), and one B(1) atom. In the fifth H site, H(5) is bonded in a distorted single-bond geometry to two equivalent Na(1) and one B(2) atom. In the sixth H site, H(6) is bonded in a distorted single-bond geometry to two equivalent Na(2) and one B(2) atom.