Noncovalent interactions and photophysical properties of new Ag(I) complexes with 4-amino-2,1,3-benzothiadiazole

Abstract

New silver complexes [AgL(NO3)]n (1), [AgL2(NO3)]n (2) and [AgL3(NO3)]2 (3) (L = 4-amino-2,1,3-benzothiadiazole) were obtained as single-phase products of the reactions of AgNO3 with L by varying their ratio. The structures of 1–3 were established by single-crystal X-ray diffraction and contain {Ag2L2} units, where L acts as a bridging ligand. The other metal coordination sites are occupied by O atoms of nitrates and N atoms of L ligands. Several types of strong and weak L–L and Ag–L interactions in the complexes are discussed herein, supported by quantum chemical calculations. Differences in the structures of the complexes cause significant changes of the photoluminescence intensity: no emission for 2 and noticeable for 1 and 3. However, similar values of luminescence maxima for 1 and 3 (630 and 620 nm, respectively) result in red emission for both compounds. Structural, topological, and spectroscopic findings are interpreted on the basis of state-of-the-art quantum mechanical calculations.