Ternary Transition Metal Nitrides Research Articles

Synthesis of intermetallic nitrides by solid-state precursor reduction

Solid-state nitrides are of interest because they exhibit technologically useful properties. For example, some transition-metal nitrides are extremely hard and strong yet are good conductors of heat and electricity. Others show interesting catalytic properties, where the similarity metals has been pointed out. In this study, transition-mental molybdates FeMoO[sub 4] and NiMoO[sub 4] were used as precursors for ternary transition-metal nitrides. 42 refs., 4 figs., 3 tabs.

Synthesis and Characterization of a New Ternary Transition Metal Nitride, FeWN2, from the Transition Metal Oxide Precursor, FeWO4

AbstractThe ternary nitride, FeWN2, has been synthesized via ammonolysis of the transition metal tungstate, FeWO4. FeWN2 is hexagonal with a unit cell of a = 2.8724(1) Å and c =10.973(4) A. Rietveld refinements were performed in the space group P3–1C with Rwp=9.91%, and Rp=7.23%. The structure consist of alternating octahedrally coordinated iron-nitrogen layers and trigonal prismatically coordinated tungsten-nitrogen layers. Mössbauer data at 250K indicates an isomer shift δ=0.85 and shows no quadrupole splitting, which is consistent with the octahedral iron coordination in the proposed structure.

Investigation of ternary transition-metal nitride systems by reactive cosputtering

A reactive dc cosputtering technique has been used to evaluate compound formation in bimetallic transition-metal nitride systems. A wide range in M-M[prime] composition can be studied in a single deposition run, and the method is applicable to nonalloying metal combinations. Using this technique, it was found that [delta]-NbN and YN form a continuous (Nb,Y)N solid solution of the NaCl type, in which the superconducting transition temperature varies with the Nb:Y ratio. In the Gd-Cr-N system only limited solid solubility of CrN and GdN was found, and evidence was obtained for a new Gd-Cr-N species centered around the GdCr[sub 2] composition. This species shows a low-temperature magnetic transition. 12 refs., 5 figs.