Femto- and attosecond electron dynamics in 5'-Guanosine monophosphate interface as probed by resonant Auger spectroscopy

Ikeura, Hiromi*; Sekiguchi, Tetsuhiro  

To help in our understanding of the electron transport properties of deoxyribonucleic acid (DNA), it is useful to study the interfacial interaction between each nucleotide building block of DNA. Electron transfer properties between phosphate and groups in microcrystalline 5'-Guanosine monophosphate (GMP) were probed using energy-dependent resonant Auger spectroscopy. Results show that the phosphate group of GMP forms an extended state along the phosphate directions similar to the case of DNA phosphate backbones. Electron delocalization time of the phosphate groups in GMP is faster than those of DNA, as estimated using the core-hole clock method. This suggests that interface between GMP phosphate groups would have the lowest tunneling barrier among DNA related systems. Although the - coupling of nucleobasis is only recognized as charge-transfer pathway in DNA and related systems, another conduction pathway through phosphate groups would be possible.