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Metallophthalocyanine (MPc)-linked conductive two-dimensional (2D) metal−organic frameworks (MOFs) hold tremendous promise as modular 2D materials in sensing, catalysis, and energy-related applications due to their combinatory bimetallic system from the MPc core and bridging metal nodes, endowing them with high electrical conductivity and multifunctionality. Despite significant advances, there is a gap in fundamental understanding regarding the periodic effects of metal nodes on the structural properties of MP-linked 2D MOFs. Herein, we report a series of highly crystalline MOFs wherein copper phthalocyanine (CuPc) is linked with Ni, Cu, and Zn nodes (CuPc-O-M, M: Ni, Cu, Zn). The prepared CuPc-O-M MOFs exhibit p-type semiconducting properties with an exceptionally high range of electrical conductivity. Notably, the differences in the 3d orbital configurations of the Ni, Cu, and Zn nodes in CuPc-O-M MOFs lead to perturbations of the interlayer stacking patterns of the 2D framework materials, which ultimately affect material properties, such as semiconducting band gaps and charge transport within the framework. The Cu2+ (3d9) metal node within the eclipsed interlayer stacking of CuPc-O-Cu MOF demonstrates excellent charge transport, which results in the smallest band gap of 1.14 eV and the highest electrical conductivity of 9.3 S m−1, while the Zn2+ (3d10) metal node within CuPc-O-Zn results in a slightly inclined interlayer stacking, leading to the largest band gap of 1.27 eV and the lowest electrical conductivity of 2.9 S m−1. These findings form an important foundation in the strategic molecular design of this class of materials for multifaceted functionality that builds upon the electronic properties of these materials. 

In this work, we synthesize and study the charge transfer properties of a oligosilyl coordination polymer formed from zirconium clusters. Although the synthesized disordered polymer lacks long range order, spectroscopic and computational evidence suggest that the metal-ligand bond is formed, and the principle crystallographic reflections closely match those simulated from inter-node spacings matching that of the ligand. The porous polymer allows for the incorporation of guest molecules as demonstrated by the intercalation of tetracyanoquinodimethane (TCNQ). Charge transfer is predicted from DFT and experimentally observed by infrared spectroscopy, solid-state 29Si nuclear magnetic spectroscopy, and voltammetry. 

Abstract The field of sustainable heterogeneous catalysis is evolving rapidly, with a strong emphasis on developing catalysts that enhance efficiency. Among various heterogeneous photocatalysts, metal‐organic frameworks (MOFs) have gained significant attention for their exceptional performance in photocatalytic reactions. In this context, contrary to the conventional homogeneous iridium or ruthenium‐based photocatalysts, which face significant challenges in terms of availability, cost, scalability, and recyclability, a new Ba/Ti MOF (ACM‐4) is developed as a heterogeneous catalyst that can mimic/outperform the conventional photocatalysts, offering a more sustainable solution for efficient chemical processes. Its redox potential and triplet energy are comparable to or higher than the conventional catalysts, organic dyes, and metal semiconductors, enabling its use in both electron transfer and energy transfer applications. It facilitates a broad range of coupling reactions involving pharmaceuticals, agrochemicals, and natural products, and is compatible with various transition metals such as nickel, copper, cobalt, and palladium as co‐catalysts. The effectiveness of theACM‐4as a photocatalyst is supported by comprehensive material studies, photophysical, and recycling experiments. These significant findings underscore the potential ofACM‐4as a highly versatile and cost‐effective photoredox catalyst, providing a sustainable, one‐material solution for efficient chemical processes. 

Abstract Linker functionalization is a common route used to affect the electronic and catalytic properties of metal-organic frameworks. By either pre- or post-synthetically installing linkages with differing linker moieties the band gap, workfunction, and exciton lifetimes have been shown to be affected. One overlooked aspect of linker functionalization, however, has been the impact on the metal d -orbital energies to which they are bound. The ligand field differences should result in substantial changes in d -splitting. In this study we use density functional theory (DFT) to study the energetics of d -orbital energy tuning as a function of linker chemistry. We offer a general descriptor, linker pK a , as a tool to predict resultant band energies in metal-organic frameworks (MOFs). Our calculations reveal that simple functionalizations can affect the band energies, of primarily metal d lineage, by up to 2 eV and illustrate the significance of this band modularity using four archetypal MOFs: UiO-66, MIL-125, ZIF-8, and MOF-5. Together, we show that linker functionalization dramatically affects d -energies in MOF clusters and highlight that linker functionalization is a useful route for fine-tuning band edges centered on the metals, rather than linkers themselves.