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Abstract Silver cluster‐based solids have garnered considerable attention owing to their tunable luminescence behavior. While surface modification has enabled the construction of stable silver clusters, controlling interactions among clusters at the molecular level has been challenging due to their tendency to aggregate. Judicious choice of stabilizing ligands becomes pivotal in crafting a desired assembly. However, detailed photophysical behavior as a function of their cluster packing remained unexplored. Here, we modulate the packing pattern of Ag₁₂clusters by varying the nitrogen‐based ligand. CAM‐1 formed through coordination of the tritopic linker molecule and NC‐1 with monodentate pyridine ligand; established via non‐covalent interactions. Both the assemblies show ligand‐to‐metal‐metal charge transfer (LMMCT) based cluster‐centered emission band(s). Temperature‐dependent photoluminescence spectra exhibit blue shifts at higher temperatures, which is attributed to the extent of the thermal reverse population of the S₁state from the closely spaced T₁state. The difference in the energy gap (ΔE_ST) dictated by their assemblies played a pivotal role in the way that Ag₁₂cluster assembly in CAM‐1 manifests a wider ΔE_STand thus requires higher temperatures for reverse intersystem crossing (RISC) than assembly of NC‐1. Such assembly‐defined photoluminescence properties underscore the potential toolkit to design new cluster‐ assemblies with tailored optoelectronic properties. 

Abstract Charge‐transfer excited state (CTES) defines the ability to split photon energy into work producing redox equivalents suitable for photocatalysis. Here, we report inter‐net CTES formation within a two‐fold catenated crystalline metal–organic framework (MOF), constructed with two linkers, N,N′‐di(4‐pyridyl)‐1,4,5,8‐naphthalenetetracarboxydiimide (DPNDI) and 2,6‐dicarboxynaphthalene (NDC). The structural flexibility puts two complementary linkers from two nets in a proximal position to interact strongly. Supported by the electrochemical and steady‐state electronic spectroscopic data, this ground‐state interaction facilitates forming CTES that can be populated by direct excitation. We map the dynamics of the CTES which persists over a few nanoseconds and highlight the utilities of such relatively long‐lived CTES as enhanced conductivity of the MOF under light over that measured in dark and as a proof‐of‐the‐principle test, photo‐reduction of methyl viologen under white light.