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

Abstract

A luminescent nonanuclear terbium(III) hydroxo cluster, Tb₉(Hesa)₁₆(μ-OH)₁₀(NO₃) (Hesa: hexyl salicylate), stabilized by unique two-way phenyl ring interactions, π-π stackings (d = 3.482–3.599 Å) and C–H-π interactions (d = 2.75–3.03 Å) 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 π-π stackings, which are dramatically enhanced by hexyl groups in hexyl salicylate ligands.