Neopentyl radicals were produced via the reaction F+(CH₃)₄C→(CH₃)₃CCH ₂+HF, which was initiated by pulse radiolysis of neopentane/SF₆ gas mixtures at 298 K. The ultraviolet absorption spectrum of neopentyl radicals has been recorded over the wavelength range 220-270 nm. An absorption cross section, σ_(CH3)3CCH2 (240 nm)=(4.88±0.42) × 10^-18 cm² molecule^-1, has been obtained based on absolute yields using CH₃O₂ as a reference. The decay of neopentyl radicals was found to follow second-order kinetics in accordance with the self-reaction 2(CH₃)₃CCH₂→ products, with an absolute bimolecular rate constant of (2.1±0.2) × 10^-11 cm³ molecule^-1 s^-1 (±2σ).