Ultrafast IR spectroscopy of polymeric cytosine nucleic acids reveal the long-lived species is due to a localised state.
نویسندگان
چکیده
The decay pathways of UV-excited cytosine polymers are investigated using picosecond time-resolved infrared spectroscopy. Similar yields of a non-emissive (1)nπ* state are found in the single-stranded dC(30) polymer as in the dCMP monomer, but with a longer lifetime in the polymer (80 ps vs. 39 ps). A longer lifetime is also found in the d(CpC) dinucleotide. No evidence of excimer states is observed, suggesting that localised (1)nπ* excited states are the most significant intermediates present on the picosecond timescale.
منابع مشابه
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ورودعنوان ژورنال:
- Physical chemistry chemical physics : PCCP
دوره 14 18 شماره
صفحات -
تاریخ انتشار 2012