Silver(I)-Organic Frameworks Showing Remarkable Thermo-, Solvato- And Vapochromic Phosphorescence As Well As...

A series of isoreticular Ag(I) luminescent metal-organic frameworks (LMOFs), {[Ag₂L₂(CH₃CN)₂](X)₂} (X = ClO₄, OTf, and BF₄), has been designed, exploiting diphenyl(2-pyrazyl)phosphine (L) as a multidentate linker. At ambient temperature, these compounds emit a bright long-lived phosphorescence (λ_em = 545-555 nm) with a quantum efficiency as high as 22%, which is the highest value for phosphorescent Ag-LMOFs. The prepared LMOFs also exhibit pronounced thermochromic luminescence, reversibly changing their emission color in the 300-77 K range. These LMOFs also demonstrate prominent solvato- and vapochromic luminescence, which manifest as a reversible change in the emission properties during the removal and recovery of the coordinated and guest MeCN molecules, respectively. Moreover, we have discovered a reversible solvent-driven 3D-to-0D transformation of the framework {[Ag₂L₂(CH₃CN)₂](ClO₄)₂} into a brightly emissive complex [Ag₄L₄(ClO₄)₄]. To the best of our knowledge, the compounds obtained are the first Ag-LMOFs that exhibit thermo-, solvato-, and vapochromic luminescence.