Picosecond absorption spectroscopy is used to examine the dynamics of the diphenylmethyl cation produced upon the 266-nm photolysis of diphenylmethyl chloride in acetonitrile. The experiments reveal that a contact ion pair is formed with a lifetime of 150 ps which decays by collapse of the ion pair to form diphenylmethyl chloride, k(1) = 3.81 X 10(9) s(-1) and ion pair separation to the solvent-separated ion pair, k(2) = 2.87 x 10(9) s(-1). The solvent-separated ion pair decays by return to the contact ion pair, k(3) = 1.31 x 10(8) s(-1), and diffusional separation to the free ion, k(4) = 7.84 X 10(8) s(-l).