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Molten mixtures of ytterbium and lithium metals can be used as fluxes for the synthesis of metal hydrides. Reactions of indium and lithium hydride in Yb/Li flux produce Yb~51In13H27 (cubic, Im-3; a = 16.218(6) A, Z = 2). Yb~51In13H27 is an analog of previously reported Ca54In13H27 which was grown from Ca/Li flux. The compound features In@Yb12@H20@Yb30 Bergman-like clusters at the corners and body centers of the cubic lattice. The clusters are connected by a hydride site and disordered ytterbium sites. Magnetic susceptibility measurements indicate the ytterbium is divalent; the compound shows diamagnetic behavior with a Curie tail at lower temperatures attributed to impurities such as traces of Yb3+ that form on crystal surfaces due to slight oxidation.

Two new tellurium-containing nitrides were grown from reactions in molten calcium and lithium. The compound Ca6Te3N2 crystallizes in space group R3̅c (a = 12.000(3)Å, c = 13.147(4)Å; Z = 6); its structure is an anti-type of rinneite (K3NaFeCl6) and 2H perovskite related oxides such as Sr3Co2O6. The compound Ca6(LixFe1-x)Te2N3 where x ≈ 0.48 forms in space group P42/m (a = 8.718(3)Å, c = 6.719(2)Å; Z = 2) with a new stuffed anti-type variant of the Tl3BiCl6 structure. Band structure calculations and easily observable red/green dichroic behavior indicate that Ca6Te3N2 is a highly anisotropic direct band gap semiconductor (Eg = 2.5 eV). Ca6(LixFe1-x)Te2N3 features isolated linear N-Fe-N units with iron in the rare Fe(1+) state. The magnetic behavior of the iron site was characterized by magnetic susceptibility measurements, which indicate a very high magnetic moment (5.16μB) likely due to a high degree of spin-orbit coupling. Inherent disorder at the Fe/Li mixed site frustrates long-range communication between magnetic centers.

Reactions of indium and silicon with lithium nitride in Ca/Li flux produce two new nitridosilicates: Ca

Two new complex main-group metal carbides were synthesized from reactions of indium, carbon, and a metal hydride in metal flux mixtures of an alkaline earth (AE = Ca, Ba) and lithium. Ca(12)InC(13-x) and Ba(12)InC(18)H(4) both crystallize in cubic space group Im3̅ [a = 9.6055(8) and 11.1447(7) Å, respectively]. Their related structures are both built on a body-centered-cubic array of icosahedral clusters comprised of an indium atom and 12 surrounding alkaline-earth cations; these clusters are connected by bridging monatomic anions (either H(-) or C(4-)) and allenylide anions, C(3)(4-). The allenylide anions were characterized by Raman spectroscopy and hydrolysis studies. Density of states and crystal orbital Hamilton population calculations confirm that both compounds are metallic.