Charge Order and Tilt Modulation in Multiferroic KxMIIxMIII1-xF3(0.4 <x< 0.6) Transition Metal Fluorides with Tetragonal Tungsten Bronze Structure

Charge Order and Tilt Modulation in Multiferroic KxMIIxMIII1-xF3(0.4 <x< 0.6) Transition Metal Fluorides with Tetragonal Tungsten Bronze Structure