Multiple Coulomb phase in CsNiCrF6

The compound CsNiCrF6 hosts multiple Coulomb phases. A Coulomb phase is a material in which a relationship can be identified between some part of the material's structure and a field in which all the lines make closed loops (i.e. it is non-divergent). Magnetic Coulomb phases, in which the arrangements of magnetic moments are described by a non-divergent field are known, e.g. spin ice, but structural Coulomb phases are also possible. CsNiCrF6 is proposed to host Coulomb phase correlations in two elements of its crystal structure and in its magnetic moments. Here we propose to use SXD to measure Bragg and diffuse scattering that can be used to better control our modelling of the structural Coulomb phases, essential to understand the microscopic interactions that produce the magnetic Coulomb phase, and thermodynamic properties such as anomalous glass-like thermal conductivity.