Yields (in μmol/J) of products in 1 and 2 after irradiation at (above) and 293 K (below). Yields were determined from the slopes of the least-squares lines fit to the dose response data. The errors, given in parentheses, are the standard deviations derived from the linear fits to these data. The oligomer sequences are given using standard notation, reading from left-to-right 5′-to-3′. Arrows emanate from the side of the phosphodiester bond that is cleaved. At the base of an arrow, the yield is given for the oligomer that the arrow points toward. For example, irradiation of 1 at 4 K gives the following products and yields in μmol/J: pG2pC3pG4 is 0.052, C1p is 0.025, pC3pG4 is 0.019, etc. The totals refer to the sum of strand breaks due to cleavage of both 3′- and 5′-phosphodiester bonds originating from damage at each residue. A total of 5 and 4 samples were used to determine yields of 1 at 4 and 293 K respectively, and 9 and 14 samples for 2 at 4 and 293 K, respectively.