Magnesium borohydride: synthesis and crystal structure.

Figure 2. Raman spectra of Mg(BH(D)4)2 (in red) and LiBH(D)4 (in blue). Upper curves: deuteride, lower curves: hydride. The asterisk indicates a band resulting from residual diethyl-ether. Figure 5. Structure of Mg(BH4)2 viewed along the hexagonal b axis, showing two unit cells. Red (partially transparent) tetrahedra are BH4units; Mg atoms in blue. Considering the cations as A and the tetrahedral anions as B, the resulting threedimensional framework, in which each tetrahedron AB4 shares all of its vertices with another tetrahedron, resembles the frameworks of oxides and aluminosilicates, which generally display nearly linear A-B-A fragments.