Two Germanide Hydride Phases Grown in Calcium‐Rich Flux: Use of Interstitial Elements for Discovery of New Phases

Abstract

Abstract Reactions of germanium in calcium/lithium flux yield crystals of new complex hydrides, with hydrogen incorporated either inadvertently due to traces of hydride contaminants in the flux metals, or deliberately by the addition of CaH 2 as a reactant. The new germanide hydride Zintl phase LiCa 7 Ge 3 H 3 crystallizes in the orthorhombic space group Pnma [ a = 9.8599(2) Å, b = 13.7716(3) Å, c = 8.7430(2) Å; Z = 4; R 1 = 0.0195]. The structure features isolated Ge 4– anions surrounded by calcium ions, and hydride anions in octahedral sites defined by Ca and Li ions. Another product thatappears in these reactions was found to form from incorporation of both oxide and hydride impurities. This phase,LiCa 11 Ge 3 OH x ( x ≈ 4) forms in the tetragonal space group P 4 2 / nmc [ a = 15.832(2) Å, c = 13.694(2) Å; Z = 8; R 1 = 0.0350]. In addition to isolated Ge 4– and octahedral H – anions, the structure also features incorporation of oxide anions in octahedral sites.