Transient behaviors of benzophenone (BP) and several substituted benzophenones in the higher triplet excited state (T-n, n > 2) were investigated by two-color two-laser excitation technique. Energy transfer from BP(T-n) to quenchers (Q) having higher E-T1 than that of BP and the second energy transfer from Q(T-1) to BP(S-0) were observed. The lifetime of BP(T-n) is estimated to be 450 ps which is long enough for a bimolecular reaction to occur. The decay of Q(T-1) depended on the concentration and structure of the Q. BP(T-n)-sensitized cleavages of C-Cl bond of CCl4 and C-Br bond of bromobenzene occurred. (C) 2003 Elsevier Science B.V. All rights reserved.