Synthesis and Crystal Structure of a New Layered Carbide ZrAl4C4

Abstract

A new ternary layered carbide, ZrAl4C4, has been synthesized and characterized by X‐ray powder diffraction. The crystal structure was successfully determined using direct methods and further refined by the Rietveld method. The crystal is trigonal (space groupP3m1,Z=2) with lattice dimensionsa=0.332471(3) nm,c=2.19717(2) nm, andV=0.210330(3) nm3. The final reliability indices calculated from the Rietveld refinement wereRwp=6.56% (S=1.58),Rp=4.92%,RB=1.90%, andRF=0.98%. The compound shows an intergrowth structure with NaCl‐type [Zr2C3] thin slabs separated by Al4C3‐type [Al8C7] layers.