High-Pressure Multianvil Synthesis and Structure Refinement of Oxygen-Bearing Cubic Zirconium(IV) Nitridec

摘要

Group 4 element mononitrides (δ-MN, M = Ti, Zr, Hf) with a NaCl type structure are well known as materials with extreme hardness, high melting points, metallic behavior, and remarkable chemical resistance.'1' They are industrially used for wear and chemical protection, as diffusion layers, decorative coatings, and in microelectronic devices. For example, 8-TiN is broadly used as a monolayer or multilayer component for coating of cutting and milling tools because it considerably increases their service life.'2' In contrast to oxides of the group 4 elements, the existence of a stoichiometric nitride with cation oxidation state of 4+ was known, for a long time, only for zirconium.'3' In 2003 the novel cubic zirconium(IV) and haf-nium(IV) nitrides with a Th_3P_4-type structure (c-M_3N_4, where M = Zr or Hf) were synthesized at high pressures and temperatures using a laser-heated diamond anvil cell (LH-DAC) technique.