Silver-Rich Hybrid Framework Iodide Based on [Ag₈I₆]²⁺ Clusters Displays Low-Temperature Dual Emission and Luminescence Thermochromism

Abstract

Cluster-based framework metal iodides have diverse structures and excellent luminescence properties, and show promising applications in sensing and solid-state lighting. However, the design and synthesis of these materials remain great challenges because excess I– ions introduced into the synthesis systems decrease the condensation degree of M–I units. In this work, a new strategy is developed to control the condensation behavior of Ag–I units, and a new silver-rich cluster-based framework iodide [DabcoAg8I6(SPh)2] n (1) (Dabco = 1,4-diazabicyclo [2.2.2] octane) has been synthesized under solvothermal conditions in the presence of silver thiophenolate (AgSPh) n . Compound 1 features a three-dimensional (3-D) cluster-based framework with a pillared layer structure composed of cationic [Ag8I6]2+ clusters bridged by SPh– and Dabco, and displays low-temperature dual emission and luminescence thermochromism.

Single‐Crystal Transformation Engineering the Spin Change of Metal–Organic Frameworks via Cluster Deconstruction

“…Since silver halide clusters usually exhibit interesting photoluminescence properties, the halogeno(cyano)argentite building blocks may contribute to the broad emission band. [52][53][54] Upon warming, the normalized emission intensities at 488 nm gradually decrease, which shows different trend as compared to that of TPBA (Figure S36). Unlike the red shift of the TPBA ligand below 130 K, the maximum emission of 1 shows a bathochromic shift of 18 nm during the SCO process (Figure 5b), suggesting the spin-state dependent fluorescence.…”