Understanding the molecular dynamics in the pyrochlore-lattice compound GeCo2O4

Free molecules have been employed to describe the spin dynamics in many frustrated magnets, yet their origin remains unexplained. Here we propose a neutron diffuse scattering experiment on WISH to study the prototype pyrochlore-lattice compound GeCo2O4 in which molecular dynamics appear in both the paramagnetic phase and the long-range ordered phase. By comparing the high-resolution diffuse scattering data with the self-consistent Gaussian approximation calculations, we will be able to pin down a fundamental lattice model that may explain the effective free molecular models in GeCo2O4 and the related compounds.