Effective and efficient photoluminescence of salicylate-ligating terbium(III) clusters stabilized by multiple phenyl-phenyl interactions

A luminescent nonanuclear terbium(III) hydroxo cluster, Tb-9(Hesa)(16)(mu-OH)(10)(NO3) ( Hesa: hexyl salicylate), stabilized by unique two-way phenyl ring interactions, p-p stackings (d = 3.482-3.599 angstrom) and C-H-pi interactions (d = 2.75-3.03 angstrom) between adjacent pairs of salicylates, was structurally characterized based on X-ray analysis, and the favourable absorption change and efficient photoluminescent characteristic were rationalized as being due to J-type pi-pi stackings, which are dramatically enhanced by hexyl groups in hexyl salicylate ligands.