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Zero‐dimensional (0D) organic metal halide hybrids, in which organic and metal halide ions cocrystallize to form neutral species, are a promising platform for the development of multifunctional crystalline materials. Herein we report the design, synthesis, and characterization of a ternary 0D organic metal halide hybrid, (HMTA)₄PbMn_0.69Sn_0.31Br₈, in which the organic cationN‐benzylhexamethylenetetrammonium (HMTA⁺, C₁₃H₁₉N₄⁺) cocrystallizes with PbBr₄²⁻, MnBr₄²⁻, and SnBr₄²⁻. The wide band gap of the organic cation and distinct optical characteristics of the three metal bromide anions enabled the single‐crystalline “host–guest” system to exhibit emissions from multiple “guest” metal halide species simultaneously. The combination of these emissions led to near‐perfect white emission with a photoluminescence quantum efficiency of around 73 %. Owing to distinct excitations of the three metal halide species, warm‐ to cool‐white emissions could be generated by controlling the excitation wavelength.

 

Mononuclear heteroleptic complexes [Fe(tpma)(bimz)](ClO4)2 (1a), [Fe(tpma)(bimz)](BF4)2 (1b), [Fe(bpte)(bimz)](ClO4)2 (2a), and [Fe(bpte)(bimz)](BF4)2 (2b) (tpma = tris(2-pyridylmethyl)amine, bpte = S,S′-bis(2-pyridylmethyl)-1,2-thioethane, bimz = 2,2′-biimidazoline) were prepared by reacting the corresponding Fe(II) salts with stoichiometric amounts of the ligands. All complexes exhibit temperature-induced spin crossover (SCO), but the SCO temperature is substantially lower for complexes 1a and 1b as compared to 2a and 2b, indicating the stronger ligand field afforded by the N2S2-coordinating bpte ligand relative to the N4-coordinating tpma. Our findings suggest that ligands with mixed N/S coordination can be employed to discover new SCO complexes and to tune the transition temperature of known SCO compounds by substituting for purely N-coordinating ligands. 

Biomass-derived isosorbide (IS) was converted into a mono-glycal ( i.e. vinyl ether) derivative (Gly-IS) to investigate its efficacy for cationic polymerization. While homopolymerization was unsuccessful, likely due to the steric demand near the propagating cationic site, copolymerization with isobutyl vinyl ether (IBVE) revealed great promise for the use of Gly-IS as a rigid and sustainable comonomer. Traditional cationic methods yielded copolymers with IBVE, but the incorporation of Gly-IS was hindered by the propensity for Lewis acids to catalyze a ring-opening reaction driven by aromatization to a chiral furan analog. This reaction was discovered to be significantly sequestered through the use of metal-free photoinitiated cationic copolymerization methods that are void of Lewis acid reagents, yielding a much higher incorporation of Gly-IS (up to 42 mol%) into the copolymer. The rigidity and chirality of the Gly-IS repeating unit was found to increase the glass transition temperature ( T g ) up to 25 °C with 33 mol% incorporation at modest molar mass (10.4 kg mol −1 ) while all copolymers displayed thermal stability up to 320 °C under inert atmosphere. Due to its chiral structure, specific optical rotation [α] of the copolymer also increased with incorporation of Gly-IS. Therefore, Gly-IS presents opportunity as a sustainable and value-added comonomer to modulate the properties of common poly(vinyl ether) systems.