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The stability of hybrid organic–inorganic halide perovskite semiconductors remains a significant obstacle to their application in photovoltaics. To this end, the use of low‐dimensional (LD) perovskites, which incorporate hydrophobic organic moieties, provides an effective strategy to improve their stability, yet often at the expense of their performance. To address this limitation, supramolecular engineering of noncovalent interactions between organic and inorganic components has shown potential by relying on hydrogen bonding and conventional van der Waals interactions. Here, the capacity to access novel LD perovskite structures that uniquely assemble through unorthodox S‐mediated interactions is explored by incorporating benzothiadiazole‐based moieties. The formation of S‐mediated LD structures is demonstrated, including one‐dimensional (1D) and layered two‐dimensional (2D) perovskite phases assembled via chalcogen bonding and S–π interactions. This involved a combination of techniques, such as single crystal and thin film X‐ray diffraction, as well as solid‐state NMR spectroscopy, complemented by molecular dynamics simulations, density functional theory calculations, and optoelectronic characterization, revealing superior conductivities of S‐mediated LD perovskites. The resulting materials are applied in n‐i‐p and p‐i‐n perovskite solar cells, demonstrating enhancements in performance and operational stability that reveal a versatile supramolecular strategy in photovoltaics. [ABSTRACT FROM AUTHOR]

A diradical/biradical character of organic derivatives is one of the key aspects of contemporary research focusing on the fundamental studies followed by potential applicability relying on the unique optical, electronic, or magnetic properties assigned to unpaired electrons. A precise involvement of two p‐phenylenes into a cyclophane‐like conjugated, diatropic system creates a flexible molecule with the two different characters of both subunits (benzene and quinone) imprinting into the structure a Kekulé delocalized system. A dynamic of both carbocyclic subunits, and their mutual interaction generates a singlet open‐shell state (J=−1.25 kcal/mol) as documented spectroscopically (NMR and EPR). The extended theoretical analysis has proved a correlation between dihedral angle and the diradicaloid character that shifts from a closed‐shell singlet to an open‐shell state, eventually showing the y0=0.86 for 78 degrees and ΔEST=−0.34 kcal/mol. [ABSTRACT FROM AUTHOR]

This paper investigates the structural properties of 2,5‐bis(3‐bromophenyl)furan polymorphs, focusing on the halogen interactions and their influence on crystal mechanical properties. In this study, three different polymorphic modifications were obtained which crystallize in the orthorhombic system. Two of the polymorphs possess halogen interactions but only one exhibits elastic properties. Through X‐ray diffraction, crystallographic analysis and computational modelling, intricate bromine‐based halogen interactions and their impact on the packing arrangement and stability were revealed. The correlation between these interactions and crystal properties, including molecular arrangement and intermolecular forces, is explored. Understanding these relationships is vital for materials design and supramolecular chemistry, enabling the rational synthesis of tailored materials. [ABSTRACT FROM AUTHOR]

Platinum complexes [PtCl2(L)] L = L1, L2 with symmetrical HP (OCH2CMe2NH)2 (L1) and unsymmetrical HP(OCMe2CMe2O)(OCH2CMe2NH) (L2) hydrospirophosphorane (HSP) ligands were demonstrated to play a dual role of catalysts and cytotoxic compounds as well. The structure of new complex [PtCl2(L2)] was confirmed by physicochemical and spectroscopic methods, as well as single X‐ray diffraction studies for [PtCl2{P (OCMe2CMe2O)(OCH2CMe2NH2)}]. HSP ligand coordinated to the platinum center in bidentate κ2‐P,NH2 chelating mode of fashion. Both complexes were found to exhibit catalytic activity for Heck cross‐coupling reactions of iodobenzene with substituted styrenes, with good conversion and yield of stilbenes. Moreover, complexes have been applied as excellent catalysts for highly regioselective hydrosilylation of aromatic and aliphatic terminal olefins, and acetylenes terminal and internal as well. On the other hand, the preliminary biological studies revealed that in the presence of foretinib, drug candidate in clinical trials for the treatment of cancer, platinum complexes revealed increased synergistic effect and efficiently decreased the number of viable cells of triple negative breast cancer MDA‐MB‐231 cell line. [ABSTRACT FROM AUTHOR]

Reaction of 1,2‐di(tetrazol‐2‐yl)ethane (ebtz) with Fe(BF4)2⋅6 H2O in different nitriles yields one‐dimensional coordination polymers [Fe(ebtz)2(RCN)2](BF4)2⋅nRCN (n=2 for R=CH3 (1) and n=0 for R=C2H5 (2) C3H7 (3), C3H5 (4), CH2Cl (5)) exhibiting spin crossover (SCO). SCO in 1 and 3–5 is complete and occurs above 160 K. In 2, it is shifted to lower temperatures and is accompanied by wide hysteresis (T1/2↓=78 K, T1/2↑=123 K) and proceeds extremely slowly. Isothermal (80 K) time‐resolved single‐crystal X‐ray diffraction studies revealed a complex nature for the HS→LS transition in 2. An initial, slow stage is associated with shrinkage of polymeric chains and with reduction of volume at 77 % (in relation to the difference between cell volumes VHS−VLS) whereas only 16 % of iron(II) ions change spin state. In the second stage, an abrupt SCO occurs, associated with breathing of the crystal lattice along the direction of the Fe–nitrile bonds, while the nitriles reorient. HS→LS switching triggered by light (808 nm) reveals the coupling of spin state and nitrile orientation. The importance of this coupling was confirmed by studies of [Fe(ebtz)2(C2H5CN/C3H7CN)2](BF4)2 mixed crystals (2 a, 2 b), showing a shift of T1/2 to higher values and narrowing of the hysteresis loop concomitant with an increase of the fraction of butyronitrile. This increase reduces the capability of nitrile molecules to reorient. Density functional theory (DFT) studies of models of 1–5 suggest a particular possibility of 2 to adopt a low (140–145°) value of its Fe‐N‐C(propionitrile) angle. [ABSTRACT FROM AUTHOR]

Synthesis of a group of carbonyl rhenium coordination compounds with hydrospirophosphorane ligands was carried out and described. Different symmetrical HP(OCH2CH2NH)2L1, HP(OCH2CMe2NH)2L2, HP(OC6H4NH)2L3, and unsymmetrical ligands HP (OCMe2CMe2O)(OC6H4NH) L4 were found to coordinate to the rhenium center as bidentate P,N donor ligands yielding fac‐[ReCl (CO)3Ln], where n = 1–4. Furthermore, monodentate coordination was also observed in some cases, as was clearly presented in the case of [ReCl(CO)2(L4‐κ2P,N)(L4‐κP)] complex. All of the complexes were characterized using optical spectroscopy. Single‐crystalX‐ray diffraction was also performed in the case of fac‐[ReCl(CO)3L3], fac‐[ReCl(CO)3L4], [Re(CO)2(L2)2]Cl and [ReCl (CO)2(L4‐κ2P,N)(L4‐κP)] samples. Complexes [ReCl(CO)3L3] and [ReCl (CO)3L4], both bearing rings of conjugated double bonds within hydrospirophosphorane ligands, exhibited luminescence. Catalytic properties of rhenium complexes were assessed using the representative fac‐[ReCl (CO)3L2] complex in the dimerization reaction of terminal alkynes. An efficient and selective procedure for synthesis of the E‐enynes was developed. Coupling of (2‐chlorophenyl)acetylene was mediated by [ReCl (CO)3L2]/TBAF system with a 100% conversion rate. Different substituents within aromatic alkynes were tolerated and the resulting products were dependent on the nature of the substituents. [ABSTRACT FROM AUTHOR]

The random nonracemic formation of the platinum(IV) polysulfide tris(chelate) anionic complex (NH4)2[Pt(S5)3] ·2H2O, previously believed to be due to a crystallization-induced asymmetric transformation of the reaction product, under scrutiny turned out to be a new type of autocatalytic asymmetric synthesis. The synthesis is driven by simultaneous crystallization of the product as an enantiomorphous conglomerate. In particular, the preparation becomes chemo- and stereoselective when carried out with continuous vigorous stirring in the presence of seeds of the desired nonracemic ultimate reaction product, i.e. an autocatalyst. However, structural characterization of the randomly obtained products by means of XRD, 195Pt NMR, and ESI-MS measurements as well as X-ray single-crystal analyses, reveals the significant complexity of the reaction. Several tris(polysulfide) congeners and their stereoisomers are usually obtained, and they may even cocrystallize. All these characteristics point to the kinetic control of these autocatalytic asymmetric preparations under the applied nontrivial reaction conditions. Consequently, the composition and handedness of the products can to a large extent be controlled by seeding the reaction mixture with a small previously obtained solid sample, which contributes to the synthesis as an autocatalyst. [ABSTRACT FROM AUTHOR]

Lanthanide complexes with sulfonylamidophosphate-type ligands: dibenzyl(phenylsulfonyl)amidophosphate (HSB) and di(4-methylphenyl)-phenylsulfonyl-amidophosphate (HSK) have been synthesized and show promise as new sensitizers of visible and near-infrared luminescence. They constitute a new part of coordination chemistry for this type of ligand, creating simultaneously a new class of lanthanide complexes with π-conjugated ligands possessing the structural fragment SO2NHP(O). Two series of stable lanthanide complexes Na[Ln(SB)4] (1Ln) and Na[Ln(SK)4] (2Ln), where Ln=NdIII, EuIII, GdIII, TbIII, ErIII, YbIII, were characterized by X-ray structure analysis. The IR, absorption, emission, and excitation spectra at 293, 77, and 4 K, as well as luminescence decay times and emission quantum yields were used to characterize the complexes in the solid state. The relation between the crystal structure and its spectroscopic properties is also discussed. The influence of the π-π stacking interactions and a ligand-to-metal charge transfer state on ligand-to-metal energy transfer efficiency was demonstrated and discussed. Crystal-field lines determined from absorption and fluorescence spectra of 2Nd were used in computational analysis employing free-ion operators, one-electron crystal-field operators, and two-particle correlation crystal-field operators. The performed analysis enabled the determination of the Hamiltonian parameters and an unambiguous assignment of 85 crystal-field levels of NdIII ion with a mean error of 12.0 cm-1. [ABSTRACT FROM AUTHOR]

The crystal structure of the title compound, (C24H20As)[ReCl4O(H2O)], has been re-examined at 100 K. The complex contains distorted octa­hedral [ReOCl4(H2O)]− anions, with the Re atom and disordered aqua ligand located on a fourfold axis, and [Ph4As]+ cations with the As atom located on a fourfold inversion axis. In the anion, the terminal Re=O bond, 1.662 (2) Å, is trans to the aqua ligand and the Re—(OH2) and Re—Cl distances are 2.325 (3) and 2.3479 (5) Å, respectively. [ABSTRACT FROM AUTHOR]

The title salt, (C(12)H(12)N(4)O(2))[ReCl(6)], consists of 2,2'-[(1E,2E)-1,2-bis-(hy-droxy-imino)-ethane-1,2-di-yl]dipyridinium cations and [ReCl(6)](2-) anions which are both located on inversion centres. Each cation consists of a glyoxime moiety attached to two protonated pyridine rings in ortho positions. In the crystal, E,E isomers of the cation are observed which differ in the spatial arrangement of the pyridine rings. These rings are positionally disordered over two positions with site-occupancy factors of 0.786 (7) and 0.214 (7). The geometry of the cation is compared with that of a recently reported dipyridyl-glyoxime with the same configuration. The cations and anions are involved in a network of inter-molecular O-H⋯Cl, N-H⋯Cl and C-H⋯Cl hydrogen bonds.

The title compound, cis-[Re(C(12)H(24)O(4)P)Cl(2)O(C(18)H(15)P)], was prepared from the analogous trans isomer [Głowiak et al. (2000 ▶). Polyhedron, 19, 2667-2672] by a trans-cis isomerization reaction. The Re(V) atom adopts a distorted octa-hedral coordination geometry. Besides being coordinated by the oxide and the butano-late O atoms, the Re(V) atom is coordinated by a pair of chloride ligands and two P atoms in cis positions with respect to each other. In the crystal, adjacent mol-ecules are linked by weak C-H⋯Cl inter-actions, forming a three-dimensional network.

In the title salt, [ReO(2)(C(5)H(5)N)(4)]I(3), the cation and anion are both located on centres of symmetry. The Re(V) atom adopts a trans-ReO(2)N(4) octa-hedral coordination and short intra-molecular C-H⋯O contacts occur within the cation. In the crystal, the cations form layers perpendicular to [100] and a weak C-H⋯O inter-action links the cations.

The quinuclidinium cation of the title compound, C(7)H(14)NO(+)·Cl(-), shows a twist along the C-N pseudo-threefold axis, with N-C-C-C torsion angles of -16.0 (1), -16.9 (1) and -15.6 (1)°. The crystal structure is stabilized by N-H⋯Cl and O-H⋯Cl hydrogen bonds, forming infinite chains along the a and b axes.