The synthesis of FC(O)OONO2 is accomplished by the photolysis of a mixture of (FCO)(2), NO2, and O-2. The pure product is isolated after trap-to-trap condensation and the removal of byproducts by treatment of the crude product with O-3 and AsF5. The colorless liquid freezes at -105 degrees C; its boiling point is 32 degrees C. At 20 degrees C and a few millibars, FC(O)OONO2 decomposes in the gas phase with a half-life of 20 h. FC(O)OONO2 is characterized by vapor pressure measurements, vibrational, F-19 NMR, C-13 NMR and UV spectroscopies as well as by mass spectrometry. According to the vibrational and NMR spectra, the compound exists at room temperature only as a syn conformer. The molecular structure of FC(O)OONO2 is determined by gas electron diffraction. The molecule possesses a skew structure with a dihedral angle of phi(COON)=86.2(14)degrees. The short O-O bond (1.420(6) Angstrom) and the long N-O bond (1.514(6) Angstrom) are consistent with the chemical properties of this compound. The experimental geometry is reproduced reasonably well by quantum chemical.