Series of nonanuclear Tb(III) clusters with ligands of different length of alkyl chain groups and their photophysical properties are demonstrated. The nonanuclear Tb(III) clusters (Tb9 clusters) are composed of nine oxygen-bridged Tb(III) ions and sixteen alkyl salicylate ligands, where alkyl chain are ethyl (Tb9-Et), propyl (Tb9-Pr), butyl (Tb9-Bu), and hexyl (Tb9-Hex) groups. The luminescence properties of the Tb9 clusters are characterized by absorption spectra, emission quantum yields, and emission lifetimes. The radiative (kr) and nonradiative (knr) rate constants were calculated from their photophysical properties. Tb9-Hex have shown the highest kr (859 s-1) and lowest knr (137 s-1), owing to the tight packing due to CH-π interaction by long alkyl chains. [DOI: 10.1380/ejssnt.2015.27]
