Aliovalent anion substitution as a design concept for heteroanionic Ruddlesden–Popper hydrides

Abstract

Substituting 2 O²⁻ ⇒ N³⁻ + H⁻ in LiLa₂HO₃ yields dark-brown heteroanionic hydrides, which were synthesized by solid-state reactions from Li₃N, LaH₃ (and La₂O₃). They crystallize in the K₂NiF₄ type structure with mixed H/N sites in LiLa₂N_1.5H_2.5 and with mixed N/O sites in LiLa₂N_0.84(6)H_1.56(3)O_1.16(6). The latter is a semiconductor with small band gap and partly covalent Li–H interaction.