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Herein, the structural and spectroscopic properties of a new optical material, cubic Nd3+-doped mixed molybdato-tungstate with the chemical formula La2MoWO9, which could be employed to achieve the difficult task of fabricating transparent ceramics, were investigated. The samples in the form of micro-powders were obtained via solid-state reaction and the first translucent micro-ceramics were demonstrated. The previously studied micro-ceramics activated with Yb3+ ions showed the segregation phenomenon of a second phase, which was very rich in Yb3+ ions in the grain boundary, and thus a solution to avoid this phenomenon was sought. Currently, we are interested in the use of the Nd3+ dopant for two reasons, i.e., laser application and its role as a structural probe. This element has an ionic radius closer to that of La3+ than Yb3+, and thus substitutes La3+ better in the framework. Consequently, this was beneficial to obtain a more homogenous cubic mono-phase material, and in the next step, translucent ceramics. The fundamental analysis was conducted using complementary techniques such as XRD and TEM/SEM combined with low-temperature high-resolution spectroscopic techniques to elucidate the main features of this promising optical material. A few Nd3+ non-equivalent symmetry sites were observed, in accordance with the crystallographic analysis. Lastly, we also showed that the spectroscopic properties of the Nd3+ ion embedded in the La2MoWO9 host lattice were correlated with its initially missing crystal structure, which was solved based on the single crystal selected from the micro-crystalline form and presented for the first time. [ABSTRACT FROM AUTHOR]

Two organic–inorganic hybrid halobismuthates(III), (NH2CHNH2)3[Bi2Cl9] (FBC) and (NH2CHNH2)3[Bi2Br9] (FBB), have been prepared with their structures revealed by single-crystal X-ray diffraction at various temperatures. FBC is characterized by one-dimensional (1D) [Bi2Cl9]3−∞ anionic chains built by edge-sharing BiCl6 octahedra, whereas FBB adopts a layer structure (2D) [Bi2Br9]3−∞. Both materials were found to exhibit a rich polymorphism in the solid state. FBC undergoes two reversible phase transitions (PTs) at 218/220 K and at 123/126 K (cooling/heating), respectively, whereas for FBB also two PTs occur close together at 196/199 K and at 190/188 K. Dielectric response around the PT temperatures of FBC and FBB reflects high disorder of dipolar groups over the high temperature phases. The 'order–disorder' mechanism of these PTs is assigned to the dynamics of formamidinium cations. FBB is considered as a ferroic material exhibiting ferroelastic domains below 196 K. The molecular motions of organic cations in a wide temperature range were studied by means of 1H NMR (spin–lattice relaxation time). Presented findings will provide a new method to explore organic−inorganic multifunctional PT materials. [ABSTRACT FROM AUTHOR]

Two organic–inorganic hybrid halobismuthates(III), (NH2CHNH2)3[Bi2Cl9] (FBC) and (NH2CHNH2)3[Bi2Br9] (FBB), have been prepared with their structures revealed by single-crystal X-ray diffraction at various temperatures. FBC is characterized by one-dimensional (1D) [Bi2Cl9]3−∞ anionic chains built by edge-sharing BiCl6 octahedra, whereas FBB adopts a layer structure (2D) [Bi2Br9]3−∞. Both materials were found to exhibit a rich polymorphism in the solid state. FBC undergoes two reversible phase transitions (PTs) at 218/220 K and at 123/126 K (cooling/heating), respectively, whereas for FBB also two PTs occur close together at 196/199 K and at 190/188 K. Dielectric response around the PT temperatures of FBC and FBB reflects high disorder of dipolar groups over the high temperature phases. The 'order–disorder' mechanism of these PTs is assigned to the dynamics of formamidinium cations. FBB is considered as a ferroic material exhibiting ferroelastic domains below 196 K. The molecular motions of organic cations in a wide temperature range were studied by means of 1H NMR (spin–lattice relaxation time). Presented findings will provide a new method to explore organic−inorganic multifunctional PT materials. [ABSTRACT FROM AUTHOR]

Experimental electron density distribution of the [C(NH 2 ) 3 ] 3 [Gd(EDTA)F 2 ]·H 2 O crystal was determined. The derived experimental and theoretical (DFT) topological parameters such as ∇ 2 ρ c , ρ c , bond degree (BD), kinetics, and potential energy were used to study the nature of Gd-O, Gd-F, and Gd-N interactions. The natural charge of the Gd is 1.86; the natural configuration of the cation is [Xe]6s 0.13 4f 7.10 5d 0.83 , and the covalency of the Gd-L bond is mainly connected with the transfer of charge from the sp x ligand orbitals onto the 5d orbitals of the Gd cation. Simultaneously, the donation of charge onto the 6s and 4f orbitals occurs to a lesser extent. Moreover it was found that the donation of the ligand charges onto the Gd(III) is larger for compounds with a lower coordination number. The obtained topological parameters were analyzed in the context of the Gd(III) f-f transition properties, i.e., energy of the excited 2 S +1 L J states, Judd-Ofelt intensity parameters, and luminescence lifetimes, of 18 Gd(III) compounds with various O, N, and F donor ligands (DOTA, EDTA, CDTA, DTPA, NTA, EGTA, ODA, F - , H 2 O, and CO 3 2- ). The calculated nephelauxetic β parameter may reflect the penetration degree of electron lone pairs of ligands inside the metal basin. Finally, it was found for the first time that the sum of the Gd(III)-L bond energy (∑ E GdL ) is correlated with the position of the gravity center of the 8 S 7/2 → 2 S +1 L J transitions and increase of covalency of the Gd(III)-L bonds is associated with decrease of their bond energy. The obtained results may shed light on chemical bonding in systems containing f-elements. Such subtle differences in the covalent contribution to the Ln-L or An-L bond may tune the selectivity of the partitioning processes of lanthanides and actinides.

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., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

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(BF 4 ) 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)](BF 4 ) 2 (1), [Fe(μ-hbtz) 2 (μ-ADN)](BF 4 ) 2 (2), [Fe(μ-1ditz) 2 (GLN) 2 ](BF 4 ) 2 ·GLN (3) and [Fe(μ-1ditz) 2 (μ-SUN)](BF 4 ) 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.

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 y 0 =0.86 for 78 degrees and ΔE ST =-0.34 kcal/mol., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The new series of copper(I) coordination polymers [Cu(N-N)(μ-PTA)] n [PF 6 ] n {N-N = dmbpy ( 1 ), bpy ( 2 ), ncup ( 3 ), and phen ( 4 )} were generated by straightforward reaction in solution or through a mechanochemical route, of [Cu(MeCN) 4 ][PF 6 ] with 1,3,5-triaza-7-phosphaadamantane (PTA) and the corresponding polypyridines, namely, 5,5'-dimethyl-2,2'-bipyridine (dmbpy), 2,2'-bipyridine (bpy), 2,9-dimethyl-1,10-phenanthroline (ncup), and 1,10-phenanthroline (phen). The compounds were obtained as air-stable solids and fully characterized by IR, NMR spectroscopy, and elemental analyses. The molecular structures were confirmed by single-crystal X-ray diffraction analysis (for 1 , 2 , and 4 ), revealing infinite one-dimensional (1D) linear chains driven by μ-PTA N,P -linkers. All tested Cu(I) polymeric compounds show emission at room temperature, which was attributed to thermally activated delayed fluorescence (TADF). Evidence of the involvement of the excited singlet state in the emission process is presented. Comparing the photophysical properties of 1 and 2 as well as 3 and 4 , of which 1 and 3 have a stiffened structure, by introducing a methyl group to one of the ligands, we demonstrate how TADF properties depend on molecular rigidity. It is shown that stiffening of the structure reduces the flattening distortion around the Cu(I) center in the 3 MLCT state. As a result, the Δ E (S 1 -T 1 ) energy gap becomes smaller and the fluorescence quantum yield increases without significantly extending the emission lifetime. In particular, the Δ E (S 1 -T 1 ) values for complexes 1 and 3 are among the shortest reported in the scientific literature, 253 and 337 cm -1 , and the TADF lifetimes are τ(300 K) = 5.7 and 4.2 μs, respectively. The fluorescence quantum yields for these complexes are measured to be Φ PL (300 K) = 70 and 80%.

α-Amido sulphones have been used as useful starting materials in the preparation of C -chiral α-aminophosphonates and α-aminophosphonic acids. The developed methodology is based on a one-pot, base-catalysed in situ generation of an imine intermediate followed by addition of a phosphorus nucleophile. The presented protocol is simple and effective and can be applied to a variety of structurally diverse α-amido sulphones and phosphorus nucleophiles, leading to the desired pure products after simple crystallization in very good yields. Importantly, the use of H -phosphonate bearing a chiral auxiliary allows the reaction to be performed with high diastereoselectivity (a single diastereoisomer is generated and isolated) and the possibility of precise control of the configuration at the newly generated C -chiral centre.

A Cu(II) complex, [Cu(HL)(NO 3 )(CH 3 OH)]·CH 3 OH (1), was obtained by the reaction of Cu(NO 3 ) 2 ·3H 2 O and H2L in methanol solvent (H2L is ( E )-4-amino- N '-(2-hydroxy-3-methoxybenzylidene)benzohydrazide). H2L and compound 1 were characterized by various spectroscopic analyses and the molecular structure of [Cu(HL)(NO 3 )(CH 3 OH)]·CH 3 OH was determined by single-crystal X-ray analysis. The results indicated the product is a mononuclear Cu(II) complex and contains a free NH 2 functional group on the structure of the ligand. [Cu(HL)(NO 3 )(CH 3 OH)]·CH 3 OH was used for the preparation of a heterogeneous catalyst by supporting it on functionalized silica gel. The heterogeneous catalyst (Si-Cu) was prepared by an amidification reaction of [Cu(HL)(NO 3 )(CH 3 OH)]·CH 3 OH with functionalized silica gel. The resulting silica-supported catalyst (Si-Cu) was characterized by TGA, FT-IR, EPR, DRS, EDS, XRD, SEM and XPS analyses. Si-Cu was employed in a carbon-carbon coupling reaction and the effects of the amount of Si-Cu and temperature were investigated in the catalytic coupling. The structure of one of the products of the catalytic reactions (C 16 H 22 O 2 , CP1) was determined by single-crystal X-ray analysis, which proved the formation of a C-C bond and the production of di-acetylene by homocoupling of terminal alkyne. This catalytic system is stable and it can be reused for a coupling reaction without a significant change in its catalytic activity.

Novel heteronuclear Ir III -Cu II coordination compounds ([Ir(η 5 -Cp*)Cl 2 Pcfx-Cu(phen)](NO 3 )·1.75(CH 3 OH)·0.75(H 2 O) ( 1 ), [Ir(η 5 -Cp*)Cl 2 Pnfx-Cu(phen)](NO 3 )·1.75(CH 3 OH)·0.75(H 2 O) ( 2 ), [Ir(η 5 -Cp*)Cl 2 Plfx-Cu(phen)](NO 3 )·1.3(H 2 O)·1.95(CH 3 OH) ( 3 ), [Ir(η 5 -Cp*)Cl 2 Psfx-Cu(phen)] ( 4 )) bearing phosphines derived from fluoroquinolones, namely, sparfloxacin (Hsfx), ciprofloxacin (Hcfx), lomefloxacin (Hlfx), and norfloxacin (Hnfx), have been synthesized and studied as possible anticancer chemotherapeutics. All compounds have been characterized by electrospray ionization mass spectrometry (ESI-MS), a number of spectroscopic methods ( i . e ., IR, fluorescence, and electron paramagnetic resonance (EPR)), cyclic voltammetry, variable-temperature magnetic susceptibility measurements, and X-ray diffractometry. The coordination geometry of Ir III in all complexes adopts a characteristic piano-stool geometry with the η 5 -coordinated and three additional sites occupied by two chloride and phosphine ligands, while Cu II ions in complexes 1 and 2 form a distorted square-pyramidal coordination geometry, and in complex 3 , the coordination geometry around Cu II ions is a distorted octahedron. Interestingly, the crystal structure of [Ir(η 5 -Cp*)Cl 2 Plfx-Cu(phen)] features the one-dimensional (1D) metal-organic polymer. Liposomes loaded with redox-active and fluorescent [Ir(η 5 -Cp*)Cl 2 Pcfx-Cu(phen)] ( 1L ) have been prepared to increase water solubility and minimize serious systemic side effects. It has been proven, by confocal microscopy and an inductively coupled plasma mass spectrometry (ICP-MS) analysis, that the liposomal form of compound 1 can be effectively accumulated inside human lung adenocarcinoma and human prostate carcinoma cells with selective localization in nuclei. A cytometric analysis showed dominance of apoptosis over the other cell death types. Furthermore, the investigated nanoformulations induced changes in the cell cycle, leading to S phase arrest in a dose-dependent manner. Importantly, in vitro anticancer action on three-dimensional (3D) multicellular tumor spheroids has been demonstrated.

In the context of energy storage, the oxygen-evolution reaction (OER, 2H 2 O → O 2 + 4H + + 4e - ) through the water-oxidation reaction is a thermodynamically uphill reaction in overall water splitting. In recent years, copper(II) coordination compounds have been extensively used for the OER. However, challenges remain in finding the mechanism of the OER in the presence of these metal coordination compounds. Herein, the electrochemical OER activity is investigated in the presence of a copper(II) coordination compound at pH ≈ 7. While the investigations on finding true catalysts for the OER are focused on the working electrode, herein, for the first time, the focus is on the decomposition of copper(II) coordination compound (CuL 3 , L: 2,2'-bipyridine N , N '-dioxide) during the OER on the counter electrode toward the precipitation of copper(I) oxide and metallic Cu.

A logical construction of monomeric subunits armed with the carbonyl functionality allowing post-synthetic reactivity leads to the convergent formation of π-extended defected units activated with BBr 3 . The kinetic or thermodynamic control entraps either the pyrido[2,3- g ]quinoline or the 4,7-phenanthroline motifs doped with boron(III), which deeply modulates the optical properties.

Dion-Jacobson (DJ) iodoplumbates based on 1,4-phenylenedimethanammonium (PDMA) have recently emerged as promising light absorbers for perovskite solar cells. While PDMA is one of the simplest aromatic spacers potentially capable of forming a DJ structure based on (PDMA)A n -1 Pb n I 3 n +1 composition, the crystallographic proof has not been reported so far. Single crystal structure of a DJ phase based on PDMA is presented and high-field solid-state NMR spectroscopy is used to characterize the structure of PDMA-based iodoplumbates prepared as thin films and bulk microcrystalline powders. It is shown that their atomic-level structure does not depend on the method of synthesis and that it is ordered and similar for all iodoplumbate homologues. Moreover, the presence of lower (n) homologues in thin films is identified through UV-Vis spectroscopy, photoluminescence spectroscopy, and X-ray diffraction measurements, complemented by cathodoluminescence mapping. A closer look using cathodoluminescence shows that the micron-scale microstructure corresponds to a mixture of different layered homologues that are well distributed throughout the film and the presence of layer edge states which dominate the emission. This work therefore determines the formation of DJ phases based on PDMA as the spacer cation and reveals their properties on a multi-length scale, which is relevant for their application in optoelectronics., (© 2021 The Authors. Small published by Wiley-VCH GmbH.)

This paper presents a rapid, sensitive and precise method developed and validated for the quantification of sufentanil in biological samples using ultra-performance liquid chromatography coupled with QqQ-MS-MS. Plasma samples were extracted with simple and fast liquid-liquid extraction (ethyl acetate, pH 9). Calibration curve showed linearity in the concentration range of 0.005-30 µg/L. The lower limit of quantification was 0.010 µg/L. The most important method features are low lower limit of quantification value, simple plasma extraction and small sample volume. This method is suitable not only for evaluation of the pharmacokinetics, toxicology, bioavailability and clinical pharmacology of sufentanil but also for the detection and identification of this compound in human plasma samples for forensic purposes., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Two model porphyrin metal-organic frameworks were used for the incorporation of Rh(i) species by a post-synthetic metallation under mild conditions. As a result, new rhodium MOFs (Rh/MOFs), Rh/PCN-222 and Rh/NU-1102, were synthesized and structurally characterized. To illustrate the potential of this catalytic platform, we use Rh/MOFs as phosphine-free heterogeneous catalysts in the hydrogenation of unsaturated hydrocarbons under mild reaction conditions (30 °C and 1 atm H2). We found that for our Rh/MOFs an activation step is required during the first run of the catalytic process. The presence of Rh-CO moieties allowed us to monitor the activation pathway of the catalyst under a H2 atmosphere, by in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). After activation, the catalyst remains highly active during the subsequent catalytic cycles. This simple post-synthetic modification approach presents new possibilities for the utilization of Rh-based catalytic systems with robust porphyrin-based MOFs as supports.

Background: The aim of this study was to assess the analgesic efficacy of sufentanil in dressings after surgical treatment of burn wounds., Patients and Methods: Twenty adult patients, who underwent surgical treatment of third-degree burn wounds under general anesthesia, were included. Two of the patients underwent surgery twice. During surgery, patients received 50-100 μg fentanyl every 20-30 min and, after surgery, patients received 100 mg ketoprofen twice daily. Additionally, ten patients (group 1) received 50 μg sufentanil added to the burn wound dressings soaked in octenidine and phenoxyethanol while 10 patients (group 2) received 25 μg sufentanil added to the same dressings. The rescue analgesic, which was administered when pain intensified, was 5 mg subcutaneous morphine. Plasma sufentanil concentrations were assayed at 1, 2, 3, and 6 h after surgery completion and when pain was reported, along with pain intensity evaluation., Results: Sufentanil was not detected in the serum of any patients. Rescue morphine was given during the postoperative period (24 h) in one patient in group 1 (who underwent surgery twice) and three patients in group 2. The mean sufentanil concentration in dressings was higher in group 1 (0.13 ± 0.03) than group 2 (0.06 ± 0.03 μg/mL; p < 0.001). The group 1 patient who received rescue morphine had a sufentanil concentration of 0.10 μg/mL, which was the lowest concentration in group 1. Group 2 patients who received rescue morphine had sufentanil concentrations of at least two-fold lower (0.03-0.05 μg/mL). No adverse effects were observed., Conclusions: Sufentanil in dressings after burn wound surgery provides effective and safe analgesia and the sufentanil concentration in dressings should be ≥0.10 μg/mL in a solution of octenidine and phenoxyethanol., (Copyright © 2020. Published by Elsevier Ltd.)

A macrocyclic motif composed of carbazole and pyridine subunits linked by a carbonyl bridge (C═O) forms a skeleton with a peripheral reactivity that leads to a pinacol-like coupling activated by BBr 3 , eventually entrapping a substantially elongated C-C bond. Slightly modified conditions lead to the efficient transformation of the C═O unit to a CH 2 linker that, after exposure to air, gives a dimeric molecule with multiple bonds between two macrocyclic units, as documented in spectroscopy and X-ray analysis.

The sulfonic esters of N-oxyimides are a group of compounds with a wide range of biological activities, as well as a unique reactivity toward amines. They undergo this reaction with primary amines and other nucleophilic reagents according to a Lossen-like rearrangement. The reaction is initiated by nucleophilic attack on a carbonyl group in the succinimide ring followed by isocyanate formation, which next interacts with another nucleophile molecule forming an addition product (e.g., ureido or urethane derivative). However, the secondary amines are also susceptible to other reactions leading to products containing the maleimide ring formed by sulphonic acid elimination. In the case of tertiary amines, this reaction is predominant. To explain the phenomenon of the reactivity of the N- oxyimides toward different types of amines, we employed various spectroscopic and X-ray approaches as well as DFT calculation. Results suggest that the basicity of the amine used for the reaction plays a crucial role in the reaction mechanism that eventually dominates the entire chemical process. Moreover, we applied molecular docking to investigate the ability of the products to act as serine protease inhibitors using human leukocyte elastase (HLE)., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Kijewska, Sharfalddin, Jaremko, Cal, Setner, Siczek, Stefanowicz, Hussien, Emwas and Jaremko.)

Reaction of 1,2-di(tetrazol-2-yl)ethane (ebtz) with Fe(BF 4 ) 2 ⋅6 H 2 O in different nitriles yields one-dimensional coordination polymers [Fe(ebtz) 2 (RCN) 2 ](BF 4 ) 2 ⋅nRCN (n=2 for R=CH 3 (1) and n=0 for R=C 2 H 5 (2) C 3 H 7 (3), C 3 H 5 (4), CH 2 Cl (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 (T 1/2 ↓ =78 K, T 1/2 ↑ =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 V HS -V LS ) 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 (C 2 H 5 CN/C 3 H 7 CN) 2 ](BF 4 ) 2 mixed crystals (2 a, 2 b), showing a shift of T 1/2 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., (© 2020 Wiley-VCH GmbH.)

An amino acid containing octanuclear heterometallic {[MnCa] 2 } cluster has been synthesized, alongside a structurally-related trigonal prismatic [MnCa] 2+ cage.

Herein, we report the synthesis, characterization, crystal structure, density functional theory calculations, and water-oxidizing activity of a pivalate Mn-Ca cluster. All of the manganese atoms in the cluster are Mn(iv) ions and have a distorted MnO6 octahedral geometry. Three Mn(iv) ions together with a Ca(ii) ion and four-oxido groups form a cubic Mn3CaO4 unit which is similar to the Mn3CaO4 cluster in the water-oxidizing complex of Photosystem II. Using scanning electron microscopy, transmission electron microscopy, energy dispersive spectrometry, extended X-ray absorption spectroscopy, chronoamperometry, and electrochemical methods, a conversion into nano-sized Mn-oxide is observed for the cluster in the water-oxidation reaction.

A series of water-soluble copper(II) complexes based on 2,9-dimethyl-1,10-phenanthroline (dmphen) and mixed-ligands, containing PTA=O (1,3,5-triaza-7-phosphaadamantane-7-oxide) have been synthesized and fully characterized. Two types of complexes have been obtained, monocationic [Cu(NO 3 )(O-PTA=O)(dmphen)][PF 6 ] ( 1 ), [Cu(Cl)(dmphen) 2 ][PF 6 ] ( 2 ), and neutral [Cu(NO 3 ) 2 (dmphen)] ( 3 ). The solid-state structures of all complexes have been determined by single-crystal X-ray diffraction. Magnetic studies for the complex 1 - 3 indicated a very weak antiferromagnetic interaction between copper(II) ions in crystal lattice. Complexes were successfully evaluated for their cytotoxic activities on the normal human dermal fibroblast (NHDF) cell line and the antitumor activity using the human lung carcinoma (A549), epithelioid cervix carcinoma (HeLa), colon (LoVo), and breast adenocarcinoma (MCF-7) cell lines. Complexes 1 and 3 revealed lower toxicity to NHDF than A549 and HeLa cells, meanwhile compound 2 appeared to be more toxic to NHDF cell line in comparison to all cancer lines. Additionally, interactions between the complexes and human apo-transferrin (apo-Tf) using fluorescence and circular dichroism (CD) spectroscopy were also investigated. All compounds interacted with apo-transferrin, causing same changes of the protein conformation. Electrostatic interactions dominate in the 1 / 2 - apo- Tf systems and hydrophobic and ionic interactions in the case of 3 ., Competing Interests: The authors declare no conflict of interest.

Two organic-inorganic hybrid halobismuthates(iii), (NH2CHNH2)3[Bi2Cl9] (FBC) and (NH2CHNH2)3[Bi2Br9] (FBB), have been prepared with their structures revealed by single-crystal X-ray diffraction at various temperatures. FBC is characterized by one-dimensional (1D) [Bi2Cl9]3-∞ anionic chains built by edge-sharing BiCl6 octahedra, whereas FBB adopts a layer structure (2D) [Bi2Br9]3-∞. Both materials were found to exhibit a rich polymorphism in the solid state. FBC undergoes two reversible phase transitions (PTs) at 218/220 K and at 123/126 K (cooling/heating), respectively, whereas for FBB also two PTs occur close together at 196/199 K and at 190/188 K. Dielectric response around the PT temperatures of FBC and FBB reflects high disorder of dipolar groups over the high temperature phases. The 'order-disorder' mechanism of these PTs is assigned to the dynamics of formamidinium cations. FBB is considered as a ferroic material exhibiting ferroelastic domains below 196 K. The molecular motions of organic cations in a wide temperature range were studied by means of 1H NMR (spin-lattice relaxation time). Presented findings will provide a new method to explore organic-inorganic multifunctional PT materials.

Reaction between NiCl 2 ·6H 2 O, 2-hydroxy-4-methyl-6-phenyl-pyridine-3-amidoxime (H 2 L), benzoic acid, and M(NO 3 ) 3 ·6H 2 O (M = Gd, Y) in MeCN under basic conditions yields the complexes [Ni II 4 Gd III 5 (PhCOO) 10 (HL) 4 (HL zw ) 4 (OH) 2 (NO 3 ) 2 ]Cl·13.6MeCN·H 2 O ( 1 ·13.6MeCN·H 2 O) and [Ni II 4 Y III 5 (PhCOO) 10 (HL) 4 (HL zw ) 4 (OH) 2 (NO 3 ) 1.5 (H 2 O) 0.5 ]0.5Cl(NO 3 M 2 O ( 2 } subunit bisects the central {M 2 O). Both clusters display similar structures, consisting of a bell-shaped {Ni II 4 M III 5 } unit, in which a linear "zigzag" {Ni 4 } subunit bisects the central {M III 5 } "ring". Direct (dc) and alternating current (ac) magnetic susceptibility measurements carried out in the 2-300 K temperature range for complexes 1 and 2 revealed ferromagnetic intermolecular interactions, while heat-capacity measurements for the Gd analogue suggest that complex 1 lowers its temperature from T = 9.6 K down to 2.3 K by adiabatically demagnetizing from B i = 7 T to B f = 0.

The 1:1 reaction of trans-[Re III Cl 3 (PPh 3 ) 2 (MeCN)] with 2-(β-naphthalideneamino)-2-hydroxymethyl-1-propanol, H 3 L, in toluene gave the dinuclear complex [Re III 2 Cl 4 (HL)(PPh 3 )]·2C 7 H 8 (1·2C 7 H 8 ), while the 1:2 reaction led to the formation of complex [Re IV Cl 2 (HL)(PPh 3 )] (2). In both species, the Schiff-base ligand exists in its doubly deprotonated form, HL 2- , forming chelate rings around the metallic centers. In addition, 1·2C 7 H 8 displays a unique triple metal-to-metal bond between the two trivalent rhenium ions separated at a 2.229(1) Å bond distance, while in complex [Re IV Cl 2 (HL)(PPh 3 )] (2) the two aromatic ligands, HL 2- and PPh 3 , occupy axial positions, with the terminal Cl - ions in the trans position. Investigation of the magnetic properties revealed a Curie paramagnetic behavior ( S = 1/2) with a pronounced temperature independent paramagnetism (TIP) for 1·2C 7 H 8 and 2. Both the geometry and the electronic structure of both compounds have been studied by means of density functional theory (DFT) calculations, confirming the triplet and doublet spin ground state of the complexes and furthermore establishing an electron-rich σ 2 π 4 δ 1 δ *1 bond order of 3 for 1·2C 7 H 8 . In addition, the absorption spectrum of 1·2C 7 H 8 in CH 2 Cl 2 was simulated by means of DFT calculations and is in excellent agreement with both the crystallographic and theoretical studies. Complex 1·2C 7 H 8 is the first dinuclear rhenium complex with a triple metal-metal bond between trivalent rhenium centers.

An octahedral {DyIII6} cage within a diamagnetic {ZnII4} rectangle is reported, with magnetic relaxation studies revealing single-molecule magnet behaviour for the complex under zero external dc field with Ueff = 43 K and τo = 1 × 10-5 s.

A [NiII6DyIII] heptanuclear complex featuring a rare six-membered {NiII6} metal ring surrounding the central Dy(iii) ion is reported. Magnetic studies reveal single-molecule magnet behaviour for the complex under zero external dc field, while replacing the DyIII ion with [capital Upsilon]III or GdIII ions allows for a comprehensive understanding of the magnetic behaviour.

The reaction of [Cr3IIIO(OAc)6(H2O)3]NO3·AcOH with 2-hydroxynaphthaldehyde, 2-amino-isobutyric acid and NiCl2·6H2O in MeOH, under basic and solvothermal conditions, led to the formation of the quasi-1D coordination polymer {[CrIII2NiII(L)4(MeOH)2]}n (where L = the dianion of the Schiff base between 2-hydroxynaphthaldehyde and 2-amino-isobutyric acid), which behaves as a ferromagnetic chain, displaying slow relaxation of magnetization.

The solvothermal reaction between Cr(acac) 3 , MCl 2 ·6H 2 O (M = Ni, Co) and 2-hydroxy-4-methyl-6-phenyl-pyridine-3-amidoxime (H 2 L), under basic conditions, led to the synthesis of the heterometallic heptanuclear clusters [MCr(HL zw ) 6 (HL) 6 ]·3Cl (M = Ni, 1; Co, 2), with the nickel analogue displaying an S = 9/2 spin ground-state.

The solvothermal reaction between Ce(NO 3 ) 3 ·6H 2 O, 2-amino-isobutyric acid, 2-hydroxy-1-naphthaldehyde and 2-amino-2-methyl-1,3-propanediol in MeOH, in the presence of base, leads to the formation of a unique [CeCe ] keplerate cage.

The employment of 2-amino-isobutyric acid, Haib, and 2-hydroxy-1-naphthaldehyde, Hnaphth, in Ni II /Ln III chemistry has led to the isolation and characterization of two new isostructural 3d-4f tetradecanuclear [NiLn] clusters (Ln = Gd III , Dy III ), with the Dy analogue displaying temperature and frequency dependent out-of-phase signals, and the Gd analogue showing interesting magnetocaloric properties.

A solvothermal reaction between Ln(NO 3 ) 3 ·6H 2 O (Ln: Gd, Tb and Dy), 2-hydroxy-1-naphthaldehyde, 2-OH-naphth, and ethylenediamine, en, in MeOH in the presence of a base, NEt 3 , led to the formation of the 1D coordination polymers [Ln(L)(MeO)(MeOH) 0.5 ] n ·MeOH (Ln = Gd (1·MeOH), Tb(2), Dy (3·MeOH); H 2 L = 1,1'-((1E,1'E)-(ethane-1,2-diylbis(azanylylidene))bis(methanylylidene))bis(naphthalen-2-ol), the Schiff-base ligand derived from the condensation of 2-OH-naphth and en), while a similar reaction in an excess of NaN 3 yielded 1D coordination polymers [Ln(L)(N 3 ) 0.75 (MeO) 0.25 (MeOH)] n (Ln = Gd (4), Tb (5), Dy (6)). Finally, upon replacing ethylenediamine with o-phenylenediamine, o-phen, we managed to isolate the discrete dimers [Dy 2 (L') 3 (MeOH)]·2MeOH (7·2MeOH) and [Gd 2 (L') 3 (MeOH)]·2MeOH (8·2MeOH) (H 2 L' = 1,1'-((1E,1'E)-(1,2-phenylenebis(azanylylidene))bis(methanylylidene))bis (naphthalen-2-ol), the Schiff-base ligand from the condensation of 2-OH-naphth and o-phen). Polymers 1-3 describe one-dimensional chains, containing alternating seven- and eight-coordinate Ln III metal centers, polymers 4-6 contain eight-coordinate lanthanide ions, while in both 7 and 8 the two Ln III centers are eight- and seven-coordinate, adopting square antiprismatic and "piano-stool" geometry, respectively. The magnetocaloric properties of the three Gd III analogues were determined from magnetic measurements, yielding the magnetic entropy change -ΔS m = 21.8, 23.0 and 16.0 J kg -1 K -1 at T = 3.0 K on demagnetization of 7 T to 0, for 1, 4 and 8, respectively. The study of the magnetic properties also revealed that all three Dy III analogues (3, 6 and 7) display out-of-phase signals, therefore suggesting slow magnetic relaxation, while such behaviour was not established in the Tb III analogues.

The reaction between Dy(NO3)3·6H2O, Zn(OAc)2·4H2O, salicylaldehyde and 2-amino-isobutyric acid, in MeOH in the presence of NEt3 under solvothermal conditions, led to the isolation of the triacontanuclear mixed-metal cluster [Zn(II)12Dy(III)18(OH)30(L)12(sal)6(OAc)6(NO3)3(H2O)6](NO3)3·12MeOH·5H2O (1·12MeOH·5H2O), which displays frequency- and temperature-dependent out-of-phase magnetic susceptibility signals.

A new complex of Co(III) using an oxidative stable hydrazone ligand, CoL, was synthesized and characterized by elemental analysis, spectroscopic methods and single crystal X-ray analysis where HL is bis-[(E)-N'-(phenyl(pyridin-2-yl)methylene)]carbohydrazide. X-ray analysis revealed that the complex is mononuclear and the coordination environment around the Co(III) core is trans-[CoN4Cl2]. The catalytic activity of the complex in the oxygen reduction reaction was investigated. The complex is a highly oxidative resistant cobalt-hydrazone which can efficiently catalyze the reduction of oxygen (O2) by a weak electron donor ferrocene, (Fc), at the polarized water/1,2-dichloroethane (DCE) interface. Oxygen reduction is coupled with proton transfer from water to the organic phase to form hydrogen peroxide, which is extracted into the aqueous phase.

The use of (2-(β-naphthalideneamino)-2-hydroxymethyl-1-propanol) ligand, H3L, in Ni/Ln chemistry has led to the isolation of three new isostructural [Ni(II)6Ln(III)3] metallic cages. More specifically, the reaction of Ni(ClO4)2·6H2O, the corresponding lanthanide nitrate salt, and H3L in MeCN, under solvothermal conditions in the presence of NEt3, led to the isolation of three complexes with the formulas [Ni6Gd3(OH)6(HL)6(NO3)3]·5.75MeCN·2Et2O·1.5H2O (1·5.75MeCN·2Et2O·1.5H2O), [Ni6Dy3(OH)6(HL)6(NO3)3]·2MeCN·2.7Et2O·2.4H2O (2·2MeCN·2.7Et2O·2.4H2O), and [Ni6Er3(OH)6(HL)6(NO3)3]·5.75MeCN·2Et2O·1.5H2O (3·5.75MeCN·2Et2O·1.5H2O). The structure of all three clusters describes a [Ln(III)3] triangle capping a [Ni(II)6] trigonal prism. Direct current magnetic susceptibility studies in the 5-300 K range for complexes 1-3 reveal the different nature of the magnetic interactions within the clusters: dominant antiferromagnetic exchange interactions for the Dy(III) and Er(III) analogues and dominant ferromagnetic interactions for the Gd(III) example. Alternating current magnetic susceptibility measurements under zero external dc field displayed fully formed temperature- and frequency-dependent out-of-phase peaks for the [Ni(II)6Dy(III)3] analogue, establishing its single molecule magnetism behavior with Ueff = 24 K.

Employment of H3L (= 2-(β-naphthalideneamino)-2-hydroxymethyl-1-propanol) in mixed-metal manganese-lanthanide cluster chemistry has led to the isolation of five new octametallic heteronuclear isostructural [Mn(III)6Ln(III)2] complexes. More specifically, the reaction of Mn(ClO4)2·6H2O with H3L and the corresponding lanthanide nitrate in MeCN in the presence of a base, NEt3, yielded four complexes with the general formula [Mn(III)6Ln(III)2O2(OH)2(H2O)2(HL)6(NO3)6]·6MeCN·0.5H2O (Ln: Gd, 1·6MeCN·0.5H2O; Tb, 2·6MeCN·0.5H2O; Dy, 3·6MeCN·0.5H2O; Er, 4·6MeCN·0.5H2O). Furthermore, the Y(III) analogue, [Mn(III)6Y(III)2O2(OH)2(H2O)2(HL)6(NO3)6]·6MeCN·0.5H2O (5·6MeCN·0.5H2O), was also synthesized in the same manner. All five clusters describe a central rod-like topology consisting of four face-sharing defective cubane metallic units, forming a planar hexametallic [Mn(III)4Ln(III)2] core, which is further capped by two Mn(III) ions. Dc magnetic susceptibility studies in the 5-300 K range for complexes 1-5 reveal the presence of dominant antiferromagnetic exchange interactions within the metallic clusters, while ac magnetic susceptibility measurements show temperature and frequency dependent out-of-phase signals for the Dy(III) analogue (3·6MeCN·0.5H2O), suggesting potential single molecule magnetism character. Furthermore, the Y(III) analogue yielded a diamagnetic ground-state for the [Mn(III)6] core, thus proving that the SMM character displayed by 3·6MeCN·0.5H2O is due to the presence of the Dy(III) centres.

The adduct formation of protonated bis(N-confused porphyrin) (BNCP, 3,3'-bis(meso-tetratolyl-2-aza-21-carbaporphyrin) with chiral anions, carboxylic acids, and alcohols was studied in solution by means of (1) H NMR and circular dichroism (CD) spectroscopic analysis and DFT methods. The addition of enantiopure guests to the acidified BNCP resulted in optical activity that vanished after neutralization. Pairs of the (1) H NMR-distinguishable diastereomers were formed when enantiopure guests were applied, although a single form was observed upon the addition of the racemic mixtures in each case. Unidirectional configuration change that led to diastereomeric excess was observed in several instances. Such an excess was memorized by metalation of the adducts with AgBF4 , thus resulting in optically active silver(III) complexes of BNCP with some enantiomeric excess. Absolute configurations of BNCP cations and bis(zinc) and bis(silver(III)) complexes were determined on the basis of time-dependent (TD)-DFT calculations of their CD spectra. It was shown that some of the chiral carboxylates induced opposite directions of enantiomerization of di- and tetracations or di-/tetracation and bis(zinc) complexes. The source of the optical activity of the equimolar diastereomeric mixture of adducts is discussed., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first discrete hexanuclear metal clusters with cores adopting the M6(μ-O)12 cubo-octahedral topology have been synthesized in the course of a simple one-pot reaction. We present a new class of rhenium clusters which are the first hexanuclear rhenium complexes with 12 bridging ligands and the first clusters with octahedrally arranged Re atoms bridged only by O atoms forming a unique cube-like Re6(μ-O)12 unit. Our synthetic strategy demonstrates a new approach to the syntheses of polynuclear rhenium complexes under mild conditions. We discovered that the [Re6(μ-O)12(3-Mepy)6]BPh4 cluster compound has the ability to undergo reversible or/and quasireversible redox reactions without changing spatial structure and overall geometry. Subsequently, a reduction reaction of [Re6(μ-O)12(3-Mepy)6]BPh4 was performed successfully and almost quantitatively resulting in the formation of the molecular [Re6(μ-O)12(3-Mepy)6] complex.

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.

Employment of the artificial amino acid 2-amino-isobutyric acid, aibH, in Cu(II) and Cu(II)/Ln(III) chemistry led to the isolation and characterization of 12 new heterometallic heptanuclear [Cu(6)Ln(aib)(6)(OH)(3)(OAc)(3)(NO(3))(3)] complexes consisting of trivalent lanthanide centers within a hexanuclear copper trigonal prism (aibH = 2-amino-butyric acid; Ln = Ce (1), Pr (2), Nd (3), Sm (4), Eu (5), Gd (6), Tb (7), Dy (8), Ho (9), Er (10), Tm (11), and Yb (12)). Direct curent magnetic susceptibility studies have been carried out in the 5-300 K range for all complexes, revealing the different nature of the magnetic interactions between the 3d-4f metallic pairs: dominant antiferromagnetic interactions for the majority of the pairs and dominant ferromagnetic interactions for when the lanthanide center is Gd(III) and Dy(III). Furthermore, alternating current magnetic susceptibility studies reveal the possibility of single-molecule magnetism behavior for complexes 7 and 8. Finally, complexes 2, 5-8, 10, and 12 were analyzed using positive ion electrospray mass spectrometry (ES-MS), establishing the structural integrity of the heterometallic heptanuclear cage structure in acetonitrile.