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A mechanistic investigation of molecular solar thermal energy release by solid-state cycloreversion of dianthracenes to anthracenes reveals the integral roles of chemical and physical transformations of molecules towards the total energy release. 

Abstract Two covalent organic frameworks consisting of carbazolylene‐ethynylene shape‐persistent macrocycles with azine (MC‐COF‐1) or imine (MC‐COF‐2) linkages were synthesized via imine condensation. The obtained 2D frameworks are fully conjugated which imparts semiconducting properties. In addition, the frameworks showed high porosity with aligned accessible porous channels along the z axis, serving as an ideal platform for post‐synthetic incorporation of I₂into the channels to enable electrical conductivity. The resulting MC‐COF‐1 showed an electrical conductivity up to 7.8×10⁻⁴ S cm⁻¹at room temperature upon I₂doping with the activation energy as low as 0.09 eV. Furthermore, we demonstrated that the electrical properties of both MC‐COFs are switchable between electron‐conducting and insulating states by simply implementing doping‐regenerating cycles. The knowledge gained in this study opens new possibilities for the future development of tunable conductive 2D organic materials. 

Abstract Herein, the synthesis of Cu₃(HAB)_x(TATHB)_2‐x(HAB: hexaaminobenzene, TATHB: triaminotrihydroxybenzene) is reported. Synthetic improvement of Cu₃(TATHB)₂leads to a more crystalline framework with higher electrical conductivity value than previously reported. The improved crystallinity and analogous structure between TATHB and HAB enable the synthesis of Cu₃(HAB)_x(TATHB)_2‐xwith ligand compositions precisely controlled by precursor ratios. The electrical conductivity is tuned from 4.2 × 10⁻⁸to 2.9 × 10⁻⁵ S cm⁻¹by simply increasing the nitrogen content in the crystal lattice. Furthermore, computational calculation supports that the solid solution facilitates the band structure tuning. It is envisioned that the findings not only shed light on the ligand‐dependent structure–property relationship but create new prospects in synthesizing multicomponent electrically conductive metal‐organic frameworks (MOFs) for tailoring optoelectronic device applications.