Spatial organization in the two-species annihilation reactionA+B→0

New features of the domain structure in the two-species annihilation reaction, A+B→0, are reported. A simple scaling argument predicts that the gaps between domains grows as ${\mathit{t}}^{\mathrm{\zeta }}$ with ζ=3/8 and 1/3, respectively, in spatial dimension d=1 and 2. The average density profile in a single domain exhibits a power-law tail near the domain edge. This feature has surprising implications for the spatial correlations of same-species reactants.