Thin films of VOxFywere made by rf magnetron sputtering of V in Ar+O2+CF4. They were analyzed by Rutherford backscattering spectrometry and transmission electron microscopy. Optical and electrical properties changed within narrow temperature ranges. These results resemble those of thermochromic VO2, although VOxFyhas significantly enhanced transmittance, lowered conductance, and marginally depressed switching temperature.