Pressure-induced electron transfer in ferrimagnetic Prussian blue analogs

M\"ossbauer and magnetic susceptibility measurements were performed under pressure on three Prussian blue analogs, ${\mathrm{K}}_{0.1}{\mathrm{Co}}_{4}[{\mathrm{Fe}(\mathrm{CN})}_{6}{]}_{2.7}\ensuremath{\cdot}18{\mathrm{H}}_{2}\mathrm{O},$ ${\mathrm{K}}_{0.28}{\mathrm{Co}}_{4}[{\mathrm{Fe}(\mathrm{CN})}_{6}{]}_{2.76}\ensuremath{\cdot}18{\mathrm{H}}_{2}\mathrm{O},$ and ${\mathrm{Cs}}_{0.7}{\mathrm{Co}}_{4}[{\mathrm{Fe}(\mathrm{CN})}_{6}{]}_{2.9}\ensuremath{\cdot}16{\mathrm{H}}_{2}\mathrm{O}.$ A pressure-induced electron transfer ${\mathrm{Co}}^{2+}(S=\frac{3}{2})\ensuremath{-}{\mathrm{Fe}}^{3+}(S=\frac{1}{2})\ensuremath{\rightarrow}{\mathrm{Co}}^{3+}(S=0)\ensuremath{-}{\mathrm{Fe}}^{2+}(S=0)…