Topochemical synthesis of cation ordered double perovskite oxynitrides. Issue 16 (27th March 2017) - Ceravola, Roberta
Abstract : Sr2 FeWO6− x N x compounds with nitrogen contents up to x = 1 are prepared by topochemical ammonolysis of Sr2 FeWO6 . Sr2 FeWO5 N is antiferromagnetic with T N = 13 K and represents the first double perovskite oxynitride with high cationic order and nitrogen content. Abstract : Topochemical nitridation in ammonia at moderate temperatures of cation ordered Sr2 FeWO6 produces new antiferromagnetic double perovskite oxynitrides Sr2 FeWO6− x N x with 0 < x ≤ 1. Nitrogen introduction induces the oxidation of Fe 2+ to Fe 3+ and decreases T N from 38 K ( x = 0) to 13 K for Sr2 FeWO5 N which represents the first example of a double perovskite oxynitride with both high cationic order and nitrogen content. This synthetic approach can be extended to other cation combinations expanding the possibility of new materials in the large group of double perovskites.