Synthesis and crystal structure of LiCaGaN2

The quaternary nitride LiCaGaN2 was synthesized from the elements and an excess of sodium and gallium at 900° C in a sealed niobium tube. LiCaGaN2 is colorless and crystallizes in the monoclinic space group P21/c(Z=4) with a=5.790(1),b=6.969(1),c=5.895(1)a=5.790(1),b=6.969(1),c=5.895(1)  Å; β=90.037(5)°β=90.037(5)°. The structure contains the nitridogallate species |∞2 Ga2N2N4/2, which is formed by condensing edge-sharing GaN4 tetrahedral pairs.