Search for structural modulation lifting the orbital degeneracy in triangular AgNiO2

DOI

This proposal is part of our research programme on spin and orbital order in frustrated systems. AgNiO2 has a layered crystal structure with Jahn-Teller active Ni3+ ions forming an antiferromagnetic triangular lattice in the basal plane. Both spin and orbital order are frustrated in this geometry and unusual ground states may occur. There are two structural polytypes which differ in the stacking of NiO2 layers. We have observed a complex supercell structure in the hexagonal polytype with a novel stripe ordered magnetic ground state. Surprisingly the orbital degeneracy is lifted not by Jahn-Teller distortions as in other triangular spin-orbital systems but by charge order. Here we wish to explore the structural distortion lifting the orbital degeneracy in the rhombohedral polytype, where interlayer interactions are different and a new electronic ground state is expected.

Identifier
DOI https://doi.org/10.5286/ISIS.E.24003325
Metadata Access https://icatisis.esc.rl.ac.uk/oaipmh/request?verb=GetRecord&metadataPrefix=oai_datacite&identifier=oai:icatisis.esc.rl.ac.uk:inv/24003325
Provenance
Creator Dr Elisa Wheeler; Professor Radu Coldea; Dr Ewa Wawrzynska
Publisher ISIS Neutron and Muon Source
Publication Year 2010
Rights CC-BY Attribution 4.0 International; https://creativecommons.org/licenses/by/4.0/
OpenAccess true
Contact isisdata(at)stfc.ac.uk
Representation
Resource Type Dataset
Discipline Photon- and Neutron Geosciences
Temporal Coverage Begin 2007-12-10T10:30:20Z
Temporal Coverage End 2007-12-12T23:48:36Z