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Abstract Dimensionality plays an important role in the charge transport properties of organic semiconductors. Although three‐dimensional semiconductors, such as Si, are common in inorganic materials, imparting electrical conductivity to covalent three‐dimensional organic polymers is challenging. Now, the synthesis of a three‐dimensional π‐conjugated porous organic polymer (3D p‐POP) using catalyst‐free Diels–Alder cycloaddition polymerization followed by acid‐promoted aromatization is presented. With a surface area of 801 m ²  g ⁻¹ , full conjugation throughout the carbon backbone, and an electrical conductivity of 6(2)×10 ⁻⁴  S cm ⁻¹ upon treatment with I ₂ vapor, the 3D p‐POP is the first member of a new classmore » of permanently porous 3D organic semiconductors.« less

Dimensionality plays an important role in the charge transport properties of organic semiconductors. Although three–dimensional semiconductors, such as Si, are common in inorganic materials, imparting electrical conductivity to covalent three–dimensional organic polymers is challenging. Now, the synthesis of a three–dimensional π–conjugated porous organic polymer (3D p–POP) using catalyst–free Diels–Alder cycloaddition polymerization followed by acid–promoted aromatization is presented. With a surface area of 801 m² g^–1, full conjugation throughout the carbon backbone, and an electrical conductivity of 6(2)×10^–4 S cm^–1 upon treatment with I₂ vapor, the 3D p–POP is the first member of a new class of permanently porous 3D organicmore » semiconductors.« less

The extension of reticular chemistry concepts to electrically conductive three-dimensional metal–organic frameworks (MOFs) has been challenging, particularly for cases in which strong interactions between electroactive linkers create the charge transport pathways. Here, we report the successful replacement of tetrathiafulvalene (TTF) with a nickel glyoximate core in a family of isostructural conductive MOFs with Mn²⁺, Zn²⁺, and Cd²⁺. Different coordination environments of the framework metals lead to variations in the linker stacking geometries and optical properties. Single-crystal conductivity data are consistent with charge transport along the linker stacking direction, with conductivity values only slightly lower than those reported for the analogousmore » TTF materials. Lastly, these results serve as a case study demonstrating how reticular chemistry design principles can be extended to conductive frameworks with significant intermolecular contacts.« less

The electronic conductivity of two isostructural interdigitated coordination polymers based on a novel tetrathiafulvalene derivative and M(NCS)₂nodes (M = Fe, Co) is enhanced upon surface oxidation of the crystals by iodine.

Abstract The extension of reticular chemistry concepts to electrically conductive three‐dimensional metal–organic frameworks (MOFs) has been challenging, particularly for cases in which strong interactions between electroactive linkers create the charge transport pathways. Here, we report the successful replacement of tetrathiafulvalene (TTF) with a nickel glyoximate core in a family of isostructural conductive MOFs with Mn ²⁺ , Zn ²⁺ , and Cd ²⁺ . Different coordination environments of the framework metals lead to variations in the linker stacking geometries and optical properties. Single‐crystal conductivity data are consistent with charge transport along the linker stacking direction, with conductivity values only slightlymore » lower than those reported for the analogous TTF materials. These results serve as a case study demonstrating how reticular chemistry design principles can be extended to conductive frameworks with significant intermolecular contacts.« less

We report three electrically conductive metal–organic frameworks (MOFs) based on a tetrathiafulvalene linker and La ³⁺ .

We report the synthesis and crystal structure of a new high-temperature form of Ca₃P₂. The crystal structure was determined through Rietveld refinements of synchrotron powder x-ray diffraction data. This form of Ca₃P₂ has a crystal structure of the hexagonal Mn₅Si₃ type, with a Ca ion deficiency compared to the ideal 5:3 stoichiometry. This yields a stable, charge-balanced compound of Ca²⁺ and P^3–. We also report the observation of a secondary hydride phase, Ca₅P₃H, which again is a charge-balanced compound. The calculated band structure of Ca₃P₂ indicates that it is a three-dimensional Dirac semimetal with a highly unusual ring of Diracmore » nodes at the Fermi level. The Dirac states are protected against gap opening by a mirror plane in a manner analogous to what is seen for graphene.« less