Magnetic multipoles and correlation shortage in pyrochlore cerium stannate

Understand

Cerium electronic multipoles in trigonal symmetry viewed in magnetic neutron diffraction are investigated.

• Analytic expressions for all the magnetic multipoles, and radial integrals calculated with an established atomic code, are used to scrutinize a recent claim to have observed an octupole-ice configuration in a powder sample of pyrochlore Ce2Sn2O7.
• Three equally plausible suites of multipoles belonging to uncorrelated cerium ions give equally satisfactory accounts of the available diffraction pattern.
• Our multipoles are suitable for future experiments using Bragg diffraction from a compound that supports long-range magnetic order.