CaFeFeNbO6 - an iron-based double double perovskite

K Ji; J R Bedward; Q Li; P Manuel; C Ritter; J Paul Attfield

doi:10.1039/d3cc01115a

CaFeFeNbO₆ - an iron-based double double perovskite

Chem Commun (Camb). 2023 May 23;59(42):6371-6374. doi: 10.1039/d3cc01115a.

Authors

K Ji¹, J R Bedward¹, Q Li¹, P Manuel², C Ritter³, J Paul Attfield¹

Affiliations

¹ Centre for Science at Extreme Conditions (CSEC) and School of Chemistry, The University of Edinburgh, EH9 3FD, UK. j.p.attfield@ed.ac.uk.
² STFC Rutherford Appleton Lab, ISIS Facility, Harwell Science and Innovation Campus, Didcot, OX11 0QX, UK.
³ Institut Laue-Langevin, 38042 Grenoble Cedex, France.

PMID: 37144493
DOI: 10.1039/d3cc01115a

Abstract

Ordering of cations is important for controlling properties of ABO₃ perovskites, and CaFeFeNbO₆ is the first example of an Fe-based AA'BB'O₆ double double perovskite, with Ca²⁺/Fe²⁺ ordered on A-site columns, and Fe³⁺/Nb⁵⁺ at the octahedral B-sites. Substantial (37%) antisite disorder of the latter cations leads to spin glassy magnetism below a freezing transition at 12 K. The CaMnFeNbO₆ analogue also shows substantial cation disorder and spin glassy behaviour. Comparison of synthesis pressures for ordered materials based on different A-site transition metals, suggests that pressures of at least 14-18 GPa will be required to discover the expected plethora of double double perovskites based on A' cations smaller than Mn²⁺.