High-resolution powder diffraction study of the double trillium lattice magnet K2Co2(SO4)3

High-resolution diffraction data were collected for the double trillium lattice magnet K2Co2(SO4)3 across its structural phase transition. Peak splitting indicating of the monoclinic symmetry and the superstructure reflections have been observed. Additionally, the abrupt changes in the monoclinic angle and unit-cell volume, as well as the phase coexistence indicate the first-order nature of this structural phase transition.