Synthesis, crystal structure and optical features of new Hg–Se clusters

Hg(SePh)2 reacts respectively with the chemical mixtures HgI2/2,2′-bipyridine, HgI2/1,10-phenantroline, HgI2/triphenylphosphine and HgBr2/ 2,2′-bipyridine to give the cluster compounds [Hg4I4(SePh)4(2,2-bipy)2]·2dmf (Ph = phenyl; dmf = dimethylformamide) (1), [Hg4I2(SePh)6(phen)2] (2), [Hg8I2Se(SePh)12(dmf)2] (3) and [Hg8Br5Se(SePh)9(2,2-bipy)2] (4). The 8-membered ring 1 alternates mercury and selenium atoms. Cluster 2 presents similar structure, but contains six [Se–Ph]− units and only two iodine ions. The bulky nanoclusters 3 and 4 differ mainly with respect to the existence of terminal and bridging bromide ions in 4. With basis on the Kubelka–Munk function the optical band gap of the title compounds could be determined by measuring their UV–Vis diffuse reflectance spectra.

Graphical abstractHg(SePh)2 reacts with HgI2/2,2′-bipyridine, HgI2/1,10-phenantroline, HgI2/triphenylphosphine and HgBr2/2,2′-bipyridine to give the respective clusters [Hg4I4(SePh)4(2,2-bipy)2]·2dmf (Ph = phenyl; dmf = dimethylformamide), [Hg4I2(SePh)6(phen)2], [Hg8I2Se(SePh)12(dmf)2] (3) and [Hg8Br5Se(SePh)9(2,2-bipy)2] (4). The bulky nanoclusters 3 and 4 differ mainly with respect to the existence of terminal and bridging bromide ions in 4. The optical band gaps of the title compounds were determined by measuring their UV–Vis diffuse reflectance spectra.Figure optionsDownload full-size imageDownload as PowerPoint slide