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Two perovskite-type fluorides K2NaVF6 and (NH4)3VF6 were synthesized under mild hydrothermal conditions.The structures of the compounds were determined by means of powder X-ray diffraction analysis.The Rietveld refinement indicates that K2NaVF6 has a cubic elpasolite-type structure and crystallizes in space group Fm-3m with lattice constant a=8.3180(2) nm.(NH4)3VF6 has a cubic cryolite-type structure and crystallizes in space group Fm-3m with lattice parameter a=9.090(1) nm.The compounds were further characterized by scanning electron microscopy(SEM),thermogravimetric(TG) and differential thermal analysis(DTA).The variable temperature magnetic susceptibility of these two compounds was characterized for the first time and the result shows that the magnetic ordering is related to the crystallographic features and isolated magnetic unit with the temperature decreasing.