Electronic studies of copper complexes of nucleic acid components. Part 10. The copper (II)–guanosine 5′-dihydrogenphosphate system

Abstract

The polymeric complex [{Cu₃(guop)₃(OH₂)₈·5H₂O}_n](guop = guanosine monophosphate) has been studied by i.r., e.s.r., and electronic spectroscopy and by magnetic-susceptibility measurements. The PO₄ bonding to Cu^II in this complex does not differ much from that of other oxygen donors, and there are two sets of magnetically coupled copper(II) ions with –2J values of 130 and 15 cm^–1, respectively. Corresponding coupling paths are proposed. A value of the zero-field splitting, |D|= 0.15 cm^–1, has been obtained for the strongly coupled species.