Ternary compounds of lithium with yttrium, lanthanum, or neodymium and elements of the fifth main group in a 'filled' CaAl2Si2-type structure

Formation of crystal structure of ternary compounds with lithium and yttrium, lanthanum or neodymium and elements of the fifth main group of the composition ALi3X2/sup V/ (A = Y, La, Nd; X/sup V/ = P, As, Sb, Bi) are reported. Crystal structure determination by X-ray and neutron diffraction methods show that the compounds crystallize in a 'filled' CaAl2Si2 structure. Two Li atoms of the formula occupy the Al sites in distorted tetrahedral X/sup V/ holes of the lattice, the slightly distorted octahedral holes of the X/sup V/ atoms are filled with A and the third Li atom. (author)