Multi-Stimuli Responsive Luminescence and Domino Phase Transition of Hybrid Copper Halides with Nonlinear Optical Switching Behavior

Although phase transition materials (PTMs) under external stimuli are of great research interest duo to their rich potential applications, it is still challenging to explore multi-responsive PTMs. Herein, two different phases of organic-inorganic hybrid copper-based halides, alpha- and beta-Gua(3)Cu(2)I(5) (Gua(+)=CN3H6+), were synthesized by solvent evaporation method, which they crystalize in the noncentrosymmetric space group Fdd2 with zero-dimensional structure and centrosymmetric space group C2/c with one-dimensional metal-halogen framework, respectively. Interestingly, it is firstly demonstrated that Gua(3)Cu(2)I(5) simultaneously possesses reversible PL conversion and NLO switching properties in response to thermal stimulus. Strikingly, apart from heat, its structural phase transition can also be triggered by crystalline-phase-recognition (CPR) and mechanical force. These new findings may pave a path for future exploration of PTMs with multiple physical properties.

Automated summary

Two different phases of organic-inorganic hybrid copper-based halides, alpha- and beta-Gua(3)Cu(2)I(5), were successfully synthesized and demonstrated to possess reversible photoluminescence conversion and nonlinear optical switching properties under external stimulus. The structural phase transition can be triggered not only by heat, but also by crystalline-phase-recognition and mechanical force. These findings are of great significance for the future exploration of multi-responsive phase transition materials.