Journal of Physical Chemistry A, Vol.112, No.33, 7551-7555, 2008
LiSc(BH4)(4): A novel salt of Li+ and discrete Sc(BH4)(4)(-) complex anions
LiSc(BH4)(4) has been prepared by ball milling of LiBH4 and ScCl3. Vibrational spectroscopy indicates the presence of discrete Sc(BH4)(4)(-) ions. DFT calculations of this isolated complex ion confirm that it is a stable complex, and the calculated vibrational spectra agree well with the experimental ones. The four BH4- groups are oriented with a tilted plane of three hydrogen atoms directed to the central Sc ion, resulting in a global 8 + 4 coordination. The crystal structure obtained by high-resolution synchrotron powder diffraction reveals a tetragonal unit cell with a = 6.076 angstrom and c = 12.034 angstrom (space group P-42c). The local structure of the Sc(BH4)(4)(-) complex is refined as a distorted form of the theoretical structure. The Li ions are found to be disordered along the z axis.