Structural and Raman spectroscopic characterization of tetrapyridinesilver(I) perrhenate, [Agpy4]ReO4

Tetrapyridinesilver(I) perrhenate [Agpy4]ReO4 was synthesized, and its crystal structure and Raman spectra were elucidated at low temperatures. The crystal lattice is constructed from isolated tetrahedral cations and anions having no argentophilic interactions. Weak hydrogen bonds are formed between the oxygens of the disordered perrhenate anions and the ortho-hydrogens of the pyridine ligands. No parallel π…π stacking interactions are observed, but C-H…π interactions of the pyridine ligands within columns of cations and between the columns appeared. Correlation analysis for Ag+, pyridine ligands, and perrhenate ions was performed, and the perrhenate ion and some of the AgN4 skeleton vibrational modes and pyridine ligand modes in the Raman spectrum of [Agpy4]ReO4 were assigned.