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Reactions between 1,2-di(tetrazol-2-yl)ethane (ebtz), 1,6-di(tetrazol-2-yl)hexane (hbtz) or 1,1′-di(tetrazol-1-yl)methane (1ditz) and Fe(BF4)2 in the presence of adiponitrile (ADN), glutaronitrile (GLN) or suberonitrile (SUN) resulted in the formation of coordination polymers [Fe(μ-ebtz)2(μ-ADN)](BF4)2 (1), [Fe(μ-hbtz)2(μ-ADN)](BF4)2 (2), [Fe(μ-1ditz)2(GLN)2](BF4)2·GLN (3) and [Fe(μ-1ditz)2(μ-SUN)](BF4)2·SUN (4). It was established that the application of dinitriles allows an increase in the dimensionality of the ebtz and hbtz based systems while maintaining the structure of the polymeric units characteristic of previously studied mononitrile based analogues. In 3 and 4, regardless of the type of dinitrile coligand, the motif of 2D polymeric layers constituted by 1ditz molecules remains preserved. However, the dimensionality of 1ditz based networks is governed by the coordination modes of dinitriles. 3, based on a shorter molecule of glutaronitrile, crystallizes as a two-dimensional (2D) coordination polymer. In this compound, dinitriles coordinate monodentately or play the role of guest molecules. The substitution of glutaronitrile with suberonitrile enables the bridging of neighboring polymeric layers, resulting in a 3D network. The intentional selection of bis(tetrazoles) and dinitriles as building blocks has led, as expected, to obtaining systems with the structure of the first coordination sphere consisting of four tetrazole rings and two axially coordinated nitrile molecules. It created the conditions required for the occurrence of thermally induced spin crossover. Magnetic measurements and single crystal X-ray diffraction studies were used for the characterization of the spin crossover properties of 1–4. [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]

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]

Abstract: The reaction of the hydrospirophosphorane HP(OCMe2CMe2O)2 ligand or the five-membered cyclic hydrogen phosphonate HP(O)(OCMe2CMe2O) ligand with the ReOCl3(OPPh3)(SMe2) precursor under controlled reaction conditions led to the isolation of dimeric oxo-rhenium(V) complexes containing P(O)(OCMe2CMe2O)− moieties, represented by [ReOCl2{μ-OP(OCMe2CMe2O)}3ReOCl(OPPh3)] (1) and [ReOCl2(SMe2){μ-OP(OCMe2CMe2O)}]2 (2). The chemical composition of these complexes was established by means of NMR, IR spectroscopic methods, and based on analytical data. The relative stereochemistry of 1 and 2 was unambiguously determined by single X-ray diffraction studies. The crystal structure of 1 comprises two crystallographically independent molecules in an asymmetric unit and co-crystallised molecules of both dichloromethane and acetonitrile. Two different six-coordinated monomeric subunits, ReOCl2 and ReOCl(OPPh3), connected by three phosphonate bridges, build up the dinuclear complex 1. It exhibits an uncommon feature, a cis disposition of the triphenylphosphine oxide molecule relative to the terminal Rehe crystal structure of 2 includes four molecules, in which two equivalent rhenium subunits ReOCl2(SMe2) are linked by two P(O)(OCMe2CMe2O)− bridges. [Copyright &y& Elsevier]

Highlights: [•] We investigated reactivity of ReCl3 and ReI3 in excess of N-heterocyclic compounds. [•] Two kinds of complexes rhenium(III) and rhenium(V) were synthesized. [•] Single crystal X-ray diffraction and spectroscopic studies were performed. [Copyright &y& Elsevier]