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C25H30Cl4N6O6, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 9.2652(2) Å, b = 11.7642(3) Å, c = 14.6692(4) Å, α = 106.929(2)°, β = 99.753(2)°, γ = 98.675(2)°, V = 1473.15(7) Å3, Z = 2, R gt(F) = 0.0292, wRref (F 2) = 0.0839, T = 170 K.

C10H16N5O5.5, monoclinic, C2/c (no. 15), a = 17.7836(8) Å, b = 9.4796(4) Å, c = 15.8740(8) Å, β = 97.093(5)°, V = 2655.6(2) Å3, Z = 8, Rgt(F) = 0.0469, wRref(F2) = 0.1289, T = 170 K.

C10H16N12O6S2, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 7.6977(2) Å, b = 11.5353(3) Å, c = 11.7533(3) Å, α = 67.973(2)°, β = 87.916(2)°, γ = 88.347(2)°, V = 966.69(5) Å3, Z = 2, R gt(F) = 0.0290, wR ref(F 2) = 0.0818, T = 170K.

C14H26N10O10, monoclinic, P21 (no. 4), a = 12.3337(3) Å, b = 3.87010(10) Å, c = 24.2368(6) Å, β = 97.644(2)°, V = 1146.61(5) Å3, Z = 2, Rgt(F) = 0.0400, wRref(F2) = 0.1092, T = 170 K.

The influence of axial steric hindrance in α-diimine nickel catalysts on ethylene polymerization is paramount for enhancing the catalytic performance especially in terms of thermal stability and polymer molecular weights. In this study, a set of five nonsymmetrical 1,2-bis(arylimino)acenaphthene–nickel complexes, incorporating 2,6-bis(bis(4-fluorophenyl)methyl)-3,4,5-trimethoxyaniline and 2,4,6-trialkylaniline moieties, was prepared to tailor the catalytic attributes for ethylene polymerization. In-depth studies on the polymerization of ethylene, using two different cocatalysts and different reaction conditions, revealed exceptional catalytic activities for these precatalysts with activity levels as high as 20.3 × 106 g mol−1 h−1 at 30 °C and high molecular weights of the obtained polyethylene with adjustable branching degrees and distributions. Reactions at elevated temperatures validated the enhanced thermal stability of Ni-Me2 precatalysts, displaying a noteworthy activity of 1.4 × 106 g mol−1 h−1 at 100 °C. Polyethylene derived from more sterically hindered nickel complexes exhibited relatively higher molecular weights and branching degrees compared to less hindered analogues. This trend was consistent across mechanical and elastic properties, which ranged from 6.1 MPa to 10.6 MPa and 26% to 49%, respectively. Moreover, the manipulation of branching degree by increasing the reaction temperature led to an elastic recovery of up to 63%, indicating potential formation of thermoplastic polyethylene elastomers. [ABSTRACT FROM AUTHOR]

C24H26Cu2N8O27, triclinic, P1‾$P‾{1}$ (no. 2), a = 4.7705(1) Å, b = 14.6219(5) Å, c = 14.7418(3) Å, α = 61.225(3)°, β = 85.342(2)°, γ = 83.938(2)°, V = 895.73(5) Å3, Z = 1, Rgt(F) = 0.0485, wRref(F2) = 0.1341, T = 170.0 K.

C16H16N2O2, monoclinic, P21/c (no. 14), a = 8.6766(1) Å, b = 5.9039(1) Å, c = 13.3603(2) Å, β = 96.166(1)°, V = 680.432(17) Å3, Z = 2, Rgt(F) = 0.0395, wRref(F2) = 0.1195, T = 170 K.

C39H37CuFeOP2S2, triclinic, P1̄ (no. 2), a = 9.6132(10) Å, b = 11.5667(12) Å, c = 16.8739(18) Å, α = 99.732(2)°, β = 96.342(2)°, γ = 93.446(2)°, V = 1832.0(3) Å3, Z = 2, Rgt(F) = 0.0455, wRref(F2) = 0.1212, T = 293.0 K.

The properties and practical applications of polyethylene are closely associated with the polymer molecular weight, polydispersity, degree of branching, and the type of branches and its arrangement within microstructure. In this study, a set of structurally diverse unsymmetrical 1‐(2,6‐dibenzhydryl‐4‐hydroxylphenylimino)‐2‐(2,6‐(R)‐4‐(R1)phenylimino)acenaphthene‐nickel dibromide precatalysts (where Ni2Me [R = Me, R1 = H], Ni2Et [R = Et, R1 = H], Ni2iPr [R = iPr, R1 = H], Ni3Me [R, R1 = Me], Ni2Et,Me [R = Et, R1 = Me]) has been prepared and studied for ethylene polymerization. Molecular structure analysis of Ni2Me and Ni2Et complexes revealed distorted tetrahedral geometries at nickel. The polymerization activities are extremely high for all precatalysts upon activation with either EASC or MMAO aluminum reagents, a trend notably pronounced in the case of the EASC‐activated systems, entering activity in the range of 10 million g mol−1 h−1 at 30°C. The Ni2Me demonstrated exceptional performance at higher temperatures, achieving an activity of 2.4 × 106 g mol−1 h−1 at 100°C and generated high molecular weight polyethylene (Mw = 105 g mol−1) with narrow polymer dispersity across all reaction temperatures (Ð ≈ 1.5). High temperature 13C NMR spectra identified 97–142/1000C branches in resulting polyethylene, a feature significantly dependent on the reaction temperature. In terms of mechanical properties, stress–strain analysis indicated that polyethylene synthesized at lower temperatures displayed superior tensile strength compared with that produced at higher reaction temperatures, while a reverse trend was observed in strain recovery analysis. The high strain recovery (up to 72%) of these polyethylene highlights the characteristic properties of thermoplastic elastomers. [ABSTRACT FROM AUTHOR]

C10H16N6O3, monoclinic, P21/c$P{2}_{1}/c$ (no. 14), a = 7.2312(1) Å, b = 17.7721(3) Å, c = 11.0146(2) Å, β = 104.557°, V = 1370.08(4) Å3, Z = 4, Rgt (F) = 0.0532, wRref (F2) = 0.1537, T = 170.0 K.

C6H12N6O4, monoclinic, P21/n (no. 14), a = 7.3652(3) Å, b = 16.8683(7) Å, c = 8.3779(3) Å, β = 101.525(4)°, V = 1019.87(7) Å3, Z = 4, Rgt(F) = 0.0349, wRref(F2) = 0.1018, T = 170 K.

C22H28Cl2N4Ni, monoclinic, P21/c (no. 14), a = 9.7332(19) Å, b = 14.886(3) Å, c = 18.623(5) Å, β = 117.45(2)°, V = 2394.5(10) Å3, Z = 4, Rgt(F) = 0.0450, wRref(F2) = 0.1466, T = 293.0 K.

C17H14N2OFCl, triclinic, P1̄ (no. 2), a = 8.2387(19) Å, b = 9.764(2) Å, c = 10.644(3) Å, α = 72.023(4)°, β = 72.770(4)°, γ = 78.581(4)°, V = 772.5(3) Å3, Z = 2, Rgt(F) = 0.0444, wRref(F2) = 0.1099, T = 294.15 K.

The unprecedented development of perovskite solar cells (PSCs) makes them one of the most promising candidates for terawatt‐scale green energy production with low cost. However, the high boiling point solvents during the solution‐processed film deposition cause anisotropic crystal growth and toxic solvent vapor during high‐throughput manufacturing. Here, a dual‐component green solvent consisting of isopropyl acetate and acetonitrile is proposed to form a volatile perovskite precursor, which can realize the high‐quality perovskite thin film deposition by intermediate phase regulation. A room‐temperature stable perovskite intermediate phase is constructed with the engagement of isopropyl acetate as co‐solvent, which suppresses the exploding nucleation rate in volatile perovskite precursor, providing a fine grain growth rate and wide processing window in scalable film deposition. The corresponding PSCs fabricated by blade coating without anti‐solvents or gas quenching achieve power conversion efficiency (PCE) of 16.37 % and 15.29 % for the areas of 14.08 cm2 and 37.83 cm2, respectively. [ABSTRACT FROM AUTHOR]

Four examples of N,N-bis(aryl)butane-2,3-diimine–nickel(II) bromide complexes, [ArN=C(Me)-C(Me)=NAr]NiBr2 (where Ar = 2-(C5H9)-4,6-(CHPh2)2C6H2 (Ni1), Ar = 2-(C6H11)-4,6-(CHPh2)2C6H2 (Ni2), 2-(C8H15)-4,6-(CHPh2)2C6H2 (Ni3) and 2-(C12H23)-4,6-(CHPh2)2C6H2 (Ni4)), disparate in the ring size of the ortho-cycloalkyl substituents, were prepared using a straightforward one-pot synthetic method. The molecular structures of Ni2 and Ni4 highlight the variation in the steric hindrance of the ortho-cyclohexyl and -cyclododecyl rings exerted on the nickel center, respectively. By employing EtAlCl2, Et2AlCl or MAO as activators, Ni1–Ni4 displayed moderate to high activity as catalysts for ethylene polymerization, with levels falling in the order Ni2 (cyclohexyl) > Ni1 (cyclopentyl) > Ni4 (cyclododecyl) > Ni3 (cyclooctyl). Notably, cyclohexyl-containing Ni2/MAO reached a peak level of 13.2 × 106 g(PE) of (mol of Ni)−1 h−1 at 40 °C, yielding high-molecular-weight (ca. 1 million g mol−1) and highly branched polyethylene elastomers with generally narrow dispersity. The analysis of polyethylenes with 13C NMR spectroscopy revealed branching density between 73 and 104 per 1000 carbon atoms, with the run temperature and the nature of the aluminum activator being influential; selectivity for short-chain methyl branches (81.8% (EtAlCl2); 81.1% (Et2AlCl); 82.9% (MAO)) was a notable feature. The mechanical properties of these polyethylene samples measured at either 30 °C or 60 °C were also evaluated and confirmed that crystallinity (Xc) and molecular weight (Mw) were the main factors affecting tensile strength and strain at break (εb = 353–861%). In addition, the stress–strain recovery tests indicated that these polyethylenes possessed good elastic recovery (47.4–71.2%), properties that align with thermoplastic elastomers (TPEs). [ABSTRACT FROM AUTHOR]

Two one-dimensional oxalate-bridged Cu(II) ammonium salts, [(CH3)3NH]2[Cu(μ-C2O4)(C2O4)]·2.5H2O (I) and [(C2H5)3NH]2[Cu(μ-C2O4)(C2O4)]·H2O (II) were obtained and characterized. They were composed of ammonium: (CH3)3NH+ in (I), (C2H5)3NH+ in (II), [Cu(μ-C2O4)(C2O4)2−]n and H2O. The Jahn–Teller-distorted Cu(II) is octahedrally coordinated by six O atoms from three oxalates and forms a one-dimensional zigzag chain. The hydrogen bonds between ammonium, the anion and H2O form a three-dimensional network. There is no hydrogen bond between the anion chains. They were insulated at 20 °C with a relative humidity of 40%. Ferromagnetic and weak-ferromagnetic behaviors were observed in I and II, separately. No long-range ordering was observed above 2 K. [ABSTRACT FROM AUTHOR]