Cobalt metagermanate is one of the germanates of cobalt, with chemical formula CoGeO3. It is paramagnetic at room temperature and turns antiferromagnetic at or below 32±1 K. It exists in two crystal forms, the orthorhombic and the monoclinic. It can be prepared by the reaction of cobalt(II,III) oxide (or cobalt(II) hydroxide) and germanium dioxide at high temperatures. The chemical vapor phase transfer method can also be used for its preparation.

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Cobalt(II) compounds
Germanates