Transition-metal oxides show a diverse range of magnetic, transport, catalytic, or optical properties. In most cases, these compounds are easily prepared by high-temperature solid state reactions. However, such a thermodynamic approach allows little room for controlling coordination geometry around a transition metal that is a basis for physical properties. In my talk, I would like to demonstrate our recent attempts to develop new extended solid oxides with an unusual anionic coordination, by using various reactions at low temperatures or in controlled atmosphere.
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