title: Anomalous temperature evolution of the internal magnetic field distribution in the charge-ordered triangular antiferromagnet AgNiO2.
abstract: Zero-field muon-spin relaxation measurements of the frustrated triangular quantum magnet AgNiO2 are consistent with a model of charge disproportionation that has been advanced to explain the structural and magnetic properties of this compound. Below an ordering temperature of TN=19.9(2) K we observe six distinct muon precession frequencies, due to the magnetic order, which can be accounted for with a model describing the probable muon sites. The precession frequencies show an unusual temperature evolution which is suggestive of the separate evolution of two opposing magnetic sublattices.
authors.affiliation: Clarendon Laboratory, Oxford University Department of Physics, Parks Road, Oxford OX1 3PU, United Kingdom. t.lancaster1@physics.ox.ac.uk
authors.forename: T
authors.initials: T
authors.lastname: Lancaster
authors.forename: S J
authors.initials: SJ
authors.lastname: Blundell
authors.forename: P J
authors.initials: PJ
authors.lastname: Baker
authors.forename: M L
authors.initials: ML
authors.lastname: Brooks
authors.forename: W
authors.initials: W
authors.lastname: Hayes
authors.forename: F L
authors.initials: FL
authors.lastname: Pratt
authors.forename: R
authors.initials: R
authors.lastname: Coldea
authors.forename: T
authors.initials: T
authors.lastname: Sörgel
authors.forename: M
authors.initials: M
authors.lastname: Jansen