Co1βxβMnxβCr2βO4β crystallizes as a normal spinel in the cubic Fd3m space group, and the end members have been reported to display a
region of collinear ferrimagnetism as well as a low-temperature spin-spiral
state with variable coherence lengths from 3 nm to 10 nm in polycrystalline
samples. Here, we present the synthesis of the entire solid solution, and data
showing that the ferrimagnetic ordering temperature as well as the spin-spiral
lock-in temperature are tunable with the Co/Mn ratio. The peak magnetocaloric
entropy change was determined to be ΞSMβ = -5.63 J kgβ1 Kβ1
in an applied magnetic field change of ΞH = 0 T to 5 T for the Mn
end-member at the ferrimagnetic ordering temperature. Using density functional
theory (DFT), we explore the shortcomings of the magnetic deformation proxy to
identify trends in ΞSMβ across composition in this spinel system, and
explore future extensions of theory to address these discrepancies