  The ferrimagnetic spinel MnCr2S4 shows a variety of magnetic-field-induced
phase transitions owing to bond frustration and strong spin-lattice coupling.
However, the site-resolved magnetic properties at the respective field-induced
phases in high magnetic fields remain elusive. Our soft x-ray magnetic circular
dichroism studies up to 40 T directly evidence element-selective
magnetic-moment reorientations in the field-induced phases. The complex
magnetic structures are further supported by entropy changes extracted from
magnetocaloric-effect measurements. Moreover, thermodynamic experiments reveal
an unusual tetracritical point in the H-T phase diagram of MnCr2S4 due to
strong spin-lattice coupling.
