The interaction of the series of trivalent rare earth (RE) nitrates with 4 '-(pyridin-4-yl)-2,2 ':6 ',2 ''-terpyridine (4pytpy) was investigated. In direct reaction between RE(NO3)3 & sdot;nH2O with 4-pytpy, both, a series of isotypic complexes [RE(NO3)3(4-pytpy)(H2O)] (1a-RE with CN 10 and 1b-RE with CN 9) and the structurally individual complexes [La(NO3)3(4-pytpy)(H2O)2] (2) and [Sc(NO3)2(4-pytpy)(H2O)]NO3 (3) were obtained. The thermal stability of the phases was investigated using simultaneous differential thermal analysis and thermogravimetry (DTA/TG or STA) as well as high-temperature powder X-ray diffraction analysis (HT-PXRD). Coordinated water can be removed from complexes 1-3, resulting in the formation of coordination polymers 1 infinity[RE(NO3)3(4-pytpy)] (4-RE) for early and middle lanthanides as well as [RE(NO3)3(4-pytpy)] (5-RE) for late lanthanides, yttrium, and scandium. At elevated temperatures (150-370 degrees C), the polymeric structure 4-RE with a connection via organic linker dissociates, and a series of dimers [RE2(NO3)6(4-pytpy)2] (6-RE) bridged via nitrates are formed; the temperature of this transition reduces along the lanthanide series. In general, the accessibility of the phases and solid-state transformations depends on the ionic radius of the trivalent rare earth element. Photophysical properties of Eu3+ and Tb3+ were determined in the solid state. The absolute photoluminescence quantum yield (PLQY) of polymorphs presented here depends on the packing, which determines the ligand energy levels. Highlight is 1 infinity[Eu(NO3)3(4-pytpy)] (4-Eu) with the PLQY of 79.3(9) %. In addition to single-crystal X-ray diffraction (SCXRD), 3D electron diffraction analysis (3D-ED) was used for the determination of crystal structures.

Twelve coordination compounds ranging from polymers to complexes based on divalent ions of the 3d-transition metals Mn to Zn, and Cd together with the ligand 2-(1,2,4-1H-triazol-3-yl)pyridine (Hpt) were synthesised and fully characterised. The main products are homoleptic, one-dimensional coordination polymers 1∞[M(pt)2] (M = Mn-Zn, and Cd, pt = 3-(pyridin-2-yl)-1,2,4-triazolate), 1∞[Cu(pt)2]·0.5Py, besides complexes [MX2(Hpt)2] from MnCl2, FeCl2, CoCl2, CoBr2, ZnCl2, and Hpt = 2-(1,2,4-1H-triazol-3-yl)pyridine. In addition to these series, single crystalline by-products of the reactions were identified and their structures determined. The obtained products were investigated with single-crystal (SCXRD) and powder X-ray diffraction (PXRD), including temperature-dependent PXRD, physisorption experiments, UV-Vis, IR, and photoluminescence spectroscopy (PL), simultaneous thermal analysis, and elemental analysis. Based on 1∞[Zn(pt)2], it was possible to generate a white light-emitting compound by addition of Eu3+ and Tb3+. It follows the RGB concept with blue ligand-based emission of the coordination polymer and red/green emission of lanthanide ions and shows excitation dependent tuneable character of emission colour from blue to practically perfect white.

The intermediate compound 4′-phenyl-1′,4′-dihydro-2,2′:6′,2″-terpyridine (pdhtpy) was isolated for the first time during the synthesis of 4′-phenyl-2,2′:6′,2″-terpyridine (ptpy) and characterised by single-crystal X-ray diffraction. Pdhtpy crystallises in the triclinic crystal system with space group P1– with the following unit cell parameters at 100 K: a = 6.1325(4) Å; b = 8.2667(5) Å; c = 16.052(2) Å; α = 86.829(2)°; β = 82.507(2)°; γ = 84.603(2)°; V = 802.49(9) Å3. The absence of stabilising electron-withdrawing groups renders pdhtpy prone to oxidative conditions. Pdhtpy was obtained as a mixture with ptpy, confirmed by Rietveld refinement of the powder X-ray diffraction pattern. Notably, pdhtpy is the first solid-state 1,4-dihydropyridine lacking electron-withdrawing groups at both positions 3 and 5, distinguishing it from Hantzsch esters and related compounds.

This work addresses a comprehensive study of six new complexes of the constitution [Ln(MeDPQ)(2)Cl-3] (Ln(3+) = Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, and Y3+; MeDPQ-2-methyldipyrido-[3,2-f:2 ',3 '-h]-quinoxaline) with good thermal stability up to 446 degrees C. Statistical substitution of Sm3+, Tb3+, Gd3+, and Dy3+ with a second Ln(3+) ion led to [Ln(1-x)Ln '(x)(MeDPQ)(2)Cl-3] solid solutions, which exhibit temperature-dependent luminescent properties. Their visible emission and intensity ratios of transitions vary with temperature in the range of 253-353 K. In the case of the composition [Tb1-xEux(MeDPQ)(2)Cl-3], the maximum relative thermal sensitivity S-r values were determined as 3.77% K-1, 3.97% K-1, and 3.97% K-1 for x(Eu3+) = 0.01, 0.05, and 0.1, respectively. The compositions [Dy1-xEux(MeDPQ)(2)Cl-3] and [Tb1-xSmx(MeDPQ)(2)Cl-3] also showed significant performance. For the pair Dy3+-Eu3+, the S-r values were determined as 3.88%K-1, 3.91% K-1, and 3.80% K-1 for x(Eu) = 0.01, 0.05, and 0.1, respectively. For the pair Sm3+-Tb3+, the S-r values are 3.28% K-1 and 3.82% K-1 for x(Sm) = 0.9 and 0.1, respectively. The largest thermal sensitivity value S-r of 4.11% K-1 was achieved for the composition [Gd0.8Tb0.18Eu0.02(MeDPQ)(2)Cl-3]. In addition, patterns of thermometric performance are bound to the energy transfer efficiency Tb3+ -> Eu3+, Dy3+ -> Eu3+ -> Dy3+, and Tb3+ -> Sm3+, as this characteristic is strongly temperature-dependent in the studied range.

Complex oxides Eu2MeO6 (Me-Mo, W), Eu2W2O9 were obtained by a solid-phase reaction between binary oxides. The thermodynamic and kinetic mechanisms of the reaction processes were established using a variety of physical-chemical methods. All compounds obtained in this work crystallize in the low-symmetry monoclinic system, forming complex framework structures, which determine a set of very valuable physical-chemical properties. Comparison of experimental Kubelka-Munk functions and DFT- calculated absorption spectra shows adequate agreement and reveals the origin of the fundamental absorption. In addition, the deficiency in DFT calculations in the part of mutual contribution of CTBs of Mo-O and W-O, from one side, and Eu-O contributions, from the other side, is reported. Calculations of absorption spectra are shown to be superior to band structure analysis in the determination of optical band gaps. Additionally, luminescent properties of Eu2MeO6 and Eu2W2O9 compounds were investigated. These studies provide a better understanding of the electronic and optical properties of the compounds Eu2MeO6 and Eu2W2O9, along with their potential applications in various areas.

This study is focused on determining the refractive index as a crucial parameter for evaluating the intrinsic quantum yield and the ligand sensitisation efficiency in solid-state trivalent lanthanide coordination compounds. For this, eight trivalent europium complexes with phenyl-terpyridine ([EuX3(ptpy)(L)], X=Cl- or NO3-, ptpy=4 '-phenyl-2,2 ' : 6 ',2 ''-terpyridine, L=H2O or other molecules) were examined. Their refractive indices were determined using the Becke lines test by immersing transparent material in a series of media with known refractive indices. Using the set of media presented here, determining crystalline materials ' refractive indices from 1.41 to 1.73 with a step of 0.01 is possible. Assessment of the refractive indices of the complexes mentioned above allowed a comprehensive analysis of their photophysical properties in the solid state. Moreover, this method can be extrapolated for other solid-state materials, offering valuable insights in the broader field of photophysics. In addition to photoluminescence investigations, the compounds presented were characterised by single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), Hirschfeld surface area analysis, UV-Vis reflectance spectroscopy, hydrolysis sensitivity analysis, and simultaneous thermogravimetry and differential thermal analysis coupled with mass-spectrometry (STA-MS).

Per- and poly-fluoroalkyl substances (PFAS) are emerging contaminants of concern because of their wide use, persistence, and potential to be hazardous to both humans and the environment. Several PFAS have been designated as substances of concern; however, most PFAS in commerce lack toxicology and exposure data to evaluate their potential hazards and risks. Cardiotoxicity has been identified as a likely human health concern, and cell-based assays are the most sensible approach for screening and prioritization of PFAS. Human-induced pluripotent stem cell (iPSC)-derived cardiomyocytes are a widely used method to test for cardiotoxicity, and recent studies showed that many PFAS affect these cells. Because iPSC-derived cardiomyocytes are available from different donors, they also can be used to quantify human variability in responses to PFAS. The primary objective of this study was to characterize potential human cardiotoxic hazard, risk, and inter-individual variability in responses to PFAS. A total of 56 PFAS from different subclasses were tested in concentration-response using human iPSC-derived cardiomyocytes from 16 donors without known heart disease. Kinetic calcium flux and high-content imaging were used to evaluate biologically-relevant phenotypes such as beat frequency, repolarization, and cytotoxicity. Of the tested PFAS, 46 showed concentration-response effects in at least one phenotype and donor; however, a wide range of sensitivities were observed across donors. Inter-individual variability in the effects could be quantified for 19 PFAS, and risk characterization could be performed for 20 PFAS based on available exposure information. For most tested PFAS, toxicodynamic variability was within a factor of 10 and the margins of exposure were above 100. This study identified PFAS that may pose cardiotoxicity risk and have high inter-individual variability. It also demonstrated the feasibility of using a population-based human in vitro method to quantify population variability and identify cardiotoxicity risks of emerging contaminants.

Per- and poly-fluoroalkyl substances (PFAS) are extensively used in commerce leading to their prevalence in the environment. Due to their chemical stability, PFAS are considered to be persistent and bioaccumulative; they are frequently detected in both the environment and humans. Because of this, PFAS as a class (composed of hundreds to thousands of chemicals) are contaminants of very high concern. Little information is available for the vast majority of PFAS, and regulatory agencies lack safety data to determine whether exposure limits or restrictions are needed. Cell-based assays are a pragmatic approach to inform decision-makers on potential health hazards; therefore, we hypothesized that a targeted battery of human in vitro assays can be used to determine whether there are structure-bioactivity relationships for PFAS, and to characterize potential risks by comparing bioactivity (points of departure) to exposure estimates. We tested 56 PFAS from 8 structure-based subclasses in concentration response (0.1-100 mu M) using six human cell types selected from target organs with suggested adverse effects of PFAS - human induced pluripotent stem cell (iPSC)-derived hepatocytes, neurons, and cardiomyocytes, primary human hepatocytes, endothelial and HepG2 cells. While many compounds were without effect; certain PFAS demonstrated cell-specific activity highlighting the necessity of using a compendium of in vitro models to identify potential hazards. No class-specific groupings were evident except for some chain lengthand structure-related trends. In addition, margins of exposure (MOE) were derived using empirical and predicted exposure data. Conservative MOE calculations showed that most tested PFAS had a MOE in the 1-100 range; similar to 20% of PFAS had MOE<1, providing tiered priorities for further studies. Overall, we show that a compendium of human cell-based models can be used to derive bioactivity estimates for a range of PFAS, enabling comparisons with human biomonitoring data. Furthermore, we emphasize that establishing structure-bioactivity relationships may be challenging for the tested PFAS.

Residual lithium compounds (RLCs) are known to form on the surface of nickel-rich LiNi1-x-yCoxMnyO2 (NCM) oxides during synthesis and storage. In this study, the impact of RLCs on cathode performance in sulfide-based all-solid-state batteries (ASSBs) is investigated by employing practically relevant approaches to generate (or remove) RLCs on (or from) NCM single crystal particles. It is revealed that Li2CO3 is the predominant component in samples exposed to air. Surprisingly, heat treatment at high temperatures does not remove RLCs but increases the overall RLC content, accompanied by the partial transformation of existing RLCs into Li2O. These samples exhibit compromised electrochemical performance due to asymmetric overpotential increase during cell discharge. However, it is possible to recover performance through controlled ambient air storage which enables the conversion of existing Li2O into Li2CO3 and formation of fresh Li2CO3 on the surface. Notably, the beneficial effects are not replicated with pure CO2 or moisturized air storage, emphasizing the significance of storage conditions and reaction pathways for Li2CO3 formation. This study demonstrates that removal of Li2O residuals through the formation of Li2CO3 under controlled ambient air exposure proves to be advantageous for sulfide-based ASSBs, thereby offering valuable guidance for the development of optimized NCM-based ASSB systems. This study reveals that Li2CO3 is the predominant residual lithium compound (RLC) forming on nickel-rich NCM oxides exposed to air. High temperature annealing increases the overall RLC content due to transformation of existing RLCs into Li2O. Li2O-rich samples exhibit compromised electrochemical performance in ASSBs due to high resistance and asymmetric overpotential. Ambient air storage transforms Li2O back to Li2CO3 and recovers the performance. These findings offer valuable guidance for the development of optimized NCM-based ASSB systems. image

Elemental Te and Cd are successfully recovered from CdTe via a combinatorial process involving chemical vapor transport (CVT) using sulfur as transport agent giving elemental Te being deposited. Separation is successfully enabled by the first process for CVT of Te starting with CdTe. Cd is subsequently recovered by an oxidation of the formed CdS to CdO followed by reduction to Cd metal with natural gas, in which Cd can also be separated via the gas phase. Hereby, the process addresses the main critical elements of the active material in thin film CdTe solar cells regarding both, scarcity and toxicity. Both, closed and open systems were investigated displaying more or less thermodynamic control of the system. Transport rates were determined for the closed system as well as for an open system working with sulfur vapour at moderate temperatures below and close to the boiling point of sulfur. Excellent purity of tellurium was achieved already by the initial transport, leading to low Cd2+ concentrations in the obtained Te being below the quantification limit of microwave plasma-atomic emission spectroscopy (MP-AES) (≪0.05 wt %).

An entry from the Inorganic Crystal Structure Database, the world’s repository for inorganic crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the joint CCDC and FIZ Karlsruhe Access Structures service and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Surfactant-assisted nano-synthesis and post-synthetic modification of three archetype bulk MOFs illuminate the size-dependent morphological and photophysical property changes of nanoMOFs.

The possibility to precisely control reaction outcomes for pursuing materials with well-defined features is a main endeavor in the development of inorganic materials. Confining reactions within a confined space, such as nanoreactors, is an extremely promising methodology which allows to ensure control over the final properties of the material. An effective room temperature inverse miniemulsion approach for the controlled synthesis of undoped and Eu3+-doped calcium molybdate crystalline nanophosphors was developed. The advantages and the efficiency of confined space in terms of controlling nanoparticle features like size, shape, and functional properties are highlighted by systematically comparing miniemulsion products with calcium molybdate particles obtained without confinement from a typical batch synthesis. A relevant beneficial impact of space confinement by miniemulsion nanodroplets is observed on the control of size and shape of the final nanoparticles, resulting in 12 nm spherical nanoparticles with a narrow size distribution, as compared to the 58 nm irregularly shaped and aggregated particles from the batch approach (assessed by TEM analysis). Further considerable effects of the confined space for the miniemulsion samples are found on the doping effectiveness, leading to a more homogeneous distribution of the Eu3+ ions into the molybdate host matrix, without segregation (assessed by PXRD, XAS, and ICP-MS). These findings are finally related to the photoluminescence properties, which are evidenced to be closely dependent on the Eu(3+ )content for the miniemulsion samples, as an increase of the relative intensity of the direct f-f excitation and a shortening of the lifetime (from 0.901 ms for 1 at. % to 0.625 ms for 7 at. % samples) with increasing Eu3+ content are observed, whereas no relationship between these parameters and the Eu(3+ )content is evidenced for the batch samples. All these results are ascribed to the uniform and controlled crystallization occurring inside each miniemulsion nanodroplet, as opposed to the less controlled nucleation and growth for a classic nonconfined approach.

Correct photoluminescence quantum yield (PLQY) determination in the solid state is vital for numerous application fields, such as photovoltaics, solid lighting or the development of phosphors. In order to increase the limited number of suitable standards for such determinations, two new Ln(3+)-based complexes with 4 '-phenyl-2,2 ' : 6 ',2"-terpyridine gamma-[Ln(4)(OAc)(12)(ptpy)(2)] (1-Eu with europium and 1-Tb with terbium) are presented. The corresponding complexes show solid-state QYs of 58(4) % and 46(3) %, respectively, exhibiting broadband absorption in the UV range from 380-200 nm. As Ln(3+) ions in general exhibit narrow f-f transitions, spectral regions with a broadness of 20-35 nm can be checked. Both complexes have suitable thermal stability, up to 270 degrees C, and are stable with respect to air and humidity, for 1-Eu up to 75 % and for 1-Tb up to 53 % relative humidity. These complexes are altogether suitable as standards to increase the reliability of PLQY determination and proposed to be used for a relative PLQY determination in the solid state.

New polymorphic modifications of double sulfates β-AEu(SO4)2 (A-Rb+, Cs+) were obtained by the hydrothermal method, the structure of which differs significantly from the monoclinic modifications obtained earlier by solid-state methods. According to single-crystal diffraction data, it was found that the compounds crystallize in the orthorhombic system, space group Pnna, with parameters β-RbEu(SO4)2: a = 9.4667(4) Å, b = 13.0786(5) Å, c = 5.3760(2) Å, V = 665.61(5) Å3; β-CsEu(SO4)2: a = 9.5278(5) Å, b = 13.8385(7) Å, c = 5.3783(3) Å, V = 709.13(7) Å3. The asymmetric part of the unit cell contains one-half Rb+/Cs+ ion, one-half Eu3+ ion, both in special sites, and one SO42- ion. Both compounds exhibit nonlinear negative thermal expansion. According to the X-ray structural analysis and theoretical calculations, the polarizing effect of the alkali metal ion has a decisive influence on the demonstration of this phenomenon. Experimental indirect band gaps of β-Rb and β-Cs are 4.05 and 4.11 eV, respectively, while the direct band gaps are 4.48 and 4.54 eV, respectively. The best agreement with theoretical calculations is obtained using the ABINIT package employing PAW pseudopotentials with hybrid PBE0 functional, while norm-conserving pseudopotentials used in the frame of CASTEP code and LCAO approach in the Crystal package gave worse agreement. The properties of alkali ions also significantly affect the luminescent properties of the compounds, which leads to a strong temperature dependence of the intensity of the 5D0 → 7F4 transition in β-CsEu(SO4)2 in contrast to much weaker dependence of this kind in β-RbEu(SO4)2.

We report the multi-step synthesis of the tetradentate 2-(naphthalen-2-yl)-5-[N,N-bis(2-pyridylmethyl)aminomethyl]-1,3,4-oxadiazole ligand (LTetra-ODA) along with its corresponding [FeII(LTetra-ODA)(NCBH3)2]·1.5CH3OH (C1) complex, which is the first mononuclear 1,3,4-oxadiazole based Fe(II) spin crossover (SCO) complex, and its zinc analogue [ZnII(LTetra-ODA)(NCBH3)2]·0.5H2O (C2). The spin transition is followed by variable temperature (VT-) X-ray crystallography of [Fe(LTetra-ODA)(NCBH3)2]·1.5CH3OH (C1) at 120 and 220 K. The magnetic susceptibility measurements on the bulk sample recorded from 2 to 300 K show that the complex exhibits a complete abrupt reversible spin transition with a T1/2 of 207 K. The loss of the lattice solvent methanol shifts the T1/2 slightly to around 210 K. The spin transition in solution for [Fe(LTetra-ODA)(NCBH3)2]·1.5CH3OH (C1) was followed using the VT-1H-NMR Evans method in CD3CN, with a T1/2 of 357 K. Solid state VT luminescence studies provide some preliminary evidence of interplay of luminescence and spin transition in the [Fe(LTetra-ODA)(NCBH3)2]·1.5CH3OH (C1) complex.