Potassium Hepta Fluoro Antimonate crystals (KSb2F7 ) have been successfully grown by slow evaporation technique. Powder X-ray diffraction method has been used for structural identification. KSb2F7 crystallizes in the monoclinic system with the space group P21/c. The crystals having wide transmission spectra lying between 280 and 1100 nm. The optical characterization shows that the band gap energy of the crystal is 4.54 eV. The average refractive index in the visible region is 2.91.The peak value of optical conductivity is 4.07×1010S-1 in the UV region. The optical constants have been calculated and illustrated graphically. Thermal stability has been investigated by TGA/DTA and the melting point of the grown crystal has been found out as 252.40C. The photo conductivity study confirms the negative photo conductivity nature of the title compound.
