The decomposition temperatures of mixtures of sodium benzoate and 1,3-dimethyl-2,4,6-trinitrobenzene, 3,5＇-dimethyl-2,2＇,4,4＇,6-pentanitrobiphenyl, and 3,3＇-dimethyl-2,2＇,4,4＇,6,6＇-hexanitrobiphenyl are lower than those for the corresponding nitrocompounds. The sensitizing effect of sodium benzoate is attributed to the formation of a benzyl-type anion; this anion arising from hydrogen abstraction by the base from a methyl group in the nitrocompound. At high mole ratio of base: nitrocompound, the thermograms for mixtures containing a nitrocompound with the biphenyl moiety are explained in terms of the presence of a benzyl-type dianion.