The thermolysis of (CH3)(4)N+Br(OCF3)(2)(-) between -70 and -10 degrees C, evolving F2CO during the decomposition, gave (CH3)(4)N+BrF2-. The characterization of (CH3)(4)N+BrF2- was carried out by IR, Raman, and F-19-and C-13-NMR. For BrF2- two infrared absorption bands at 236 and 450 cm(-1) and one band in the Raman spectrum at 460 cm(-1) were observed in accord with a centrosymmetric structure. Ab initio calculations are presented for BrF2- the isoelectronic KrF2, and other related compounds with D-infinity h symmetry.