Single-stranded polynucleotides, relaxation

Our objective is to understand how the noncovalent interactions responsible for nucleic acid secondary structure (i.e. base stacking and base pairing) affect the photophysics of these multichromophoric systems. Here we describe initial experimental results that demonstrate dramatic differences in excited-state dynamics of nucleic acid polymers compared to their constituent monomers. Although ultrafast internal conversion is the dominant relaxation pathway for single bases, electronic energy relaxation in single-stranded polynucleotides... 

Several investigations have utilized P NMR to study molecular motions in double-stranded DNA. Table 1 summarizes most of the relaxation results. In all of the studies, the DNA was maintained in a double-stranded helix with no single strands or fiaying of the ends of the polynucleotide. 

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