Background/Aim: The aim of this study was to determine the value of Doppler indices and notching assessment of uterine artery between the 19th and 22nd week of gestation in the prediction of pregnancy outcome such as delivery mode, birth weight, Apgar score, afterbirth pH, fetal presentation, preeclampsia and fetal growth restriction in singleton pregnancy. Patients and Methods: This is a retrospective cohort study of Doppler ultrasound of the uterine arteries at 19-22 week of gestation in 1,472 women with singleton pregnancies. Results: Patients with bilateral high resistance-index (RI) and pulsatility-index (RI) or with the presence of a notch showed a significantly higher prevalence of small for gestational age (SGA) fetuses and intrauterine growth restriction (IUGR), low Apgar Scores at the 1st and the 5th min, high c-section rate, preterm birth, breech birth, placental insufficiency and placental abruption. The presence of a notch significantly increased the prevalence of severe preeclampsia, HELLP-syndrome and oligohydramnios. Also, patients with a bilateral uterine notching had a higher c-section rate along with higher prevalence of SGA and IUGR at screening time. Conclusion: Uterine artery Doppler waveform analysis as well as the assessment of the presence of a notch in the second trimester can be used as a screening method to identify women who will thereafter develop a severe adverse outcome.

The solvothermal synthesis of LnCl₃^.nH₂O with terephthalic acid (benzene-1,4-dicarboxylic acid, H₂BDC) produced metal–organic frameworks (LnBDC), [Ln₂(BDC)₃(H₂O)₄]_∞, where Ln = Sm, Eu, Tb, and Dy. The materials obtained were characterized by a number of physico-chemical techniques. The influence of the ionic radius of the lanthanides on the microstructural characteristics of the Ln-MOFs was evaluated by performing Rietveld refinement. The MOFs obtained were tested as fluorescent sensors for numerous cations and anions in water. The highly luminescent EuBDC and TbBDC demonstrated multi-responsive luminescence sensing functions to detect Ag(I), Fe(III), Cr(III), and Cr(VI), which are essential for their environmental applications. By applying the non-linear Stern–Volmer equation, the fluorescent quenching mechanism was determined. The stability of the obtained materials in water in a wide pH range (acidity pH = 4 and alkalinity pH = 9 solutions) was confirmed.

The luminescent metal-organic complexes of rare earth metals are advanced materials with wide application potential in chemistry, biology, and medicine. The luminescence of these materials is due to a rare photophysical phenomenon called antenna effect, in which the excited ligand transmits its energy to the emitting levels of the metal. However, despite the attractive photophysical properties and the intriguing from a fundamental point of view antenna effect, the theoretical molecular design of new luminescent metal-organic complexes of rare earth metals is relatively limited. Our computational study aims to contribute in this direction, and we model the excited state properties of four new phenanthroline-based complexes of Eu(III) using the TD-DFT/TDA approach. The general formula of the complexes is EuL₂A₃, where L is a phenanthroline with –2–CH₃O–C₆H₄, –2–HO–C₆H₄, –C₆H₅ or –O–C₆H₅ substituent at position 2 and A is Cl⁻ or NO₃⁻. The antenna effect in all newly proposed complexes is estimated as viable and is expected to possess luminescent properties. The relationship between the electronic properties of the isolated ligands and the luminescent properties of the complexes is explored in detail. Qualitative and quantitative models are derived to interpret the ligand-to-complex relation, and the results are benchmarked with respect to available experimental data. Based on the derived model and common molecular design criteria for efficient antenna ligands, we choose phenanthroline with –O–C₆H₅ substituent to perform complexation with Eu(III) in the presence of NO₃¯. Experimental results for the newly synthesized Eu(III) complex are reported with a luminescent quantum yield of about 24% in acetonitrile. The study demonstrates the potential of low-cost computational models for discovering metal-organic luminescent materials.

Heavier tetrylenes attract attention for their potential in synthesis, catalysis and small molecule activation. The coordination byN‐heterocyclic carbenes (NHCs) and cyclic (alkyl)(amino)carbenes (CAACs) results in substantial structural and electronic differences although typically only one of these yields stable derivatives for one and the same tetrylene. We now report both NHC‐ and CAAC‐coordination to a bridged bis(germylene) motif. The NHC‐coordinated bis(germylene) exhibits pyramidal germanium centers with lone pairs of electrons, while with CAAC an unprecedented stable bis(germene) with two Ge=C bonds is isolated. Spectroscopic and crystallographic evidence as well as DFT calculations confirm the effects of σ,π‐conjugation between the two germanium centers in both cases. The coordination of NHC is reversible as the reaction with BPh₃liberates the transient bis(germylene) and thus provides an alternative low‐temperature route towards polymers with Ge=Ge bonds.

Organosilanols typically show a high condensation tendency and only exist as stable isolable molecules under very specific steric and electronic conditions at the silicon atom. In the present work, various novel representatives of this class of compounds were synthesized by hydrolysis of alkoxy‐ or chlorosilanes. Phenyl, 1‐naphthyl, and 9‐phenanthrenyl substituents at the silicon atom were applied to systematically study the influence of the aromatic substituents on the structure and reactivity of the compounds. Chemical shifts in²⁹Si NMR spectroscopy in solution, correlated well with the expected electronic situation induced by the substitution pattern on the Si atom.¹H NMR studies allowed the detection of strong intermolecular hydrogen bonds. Single‐crystal X‐ray structures of the alkoxides and the chlorosilanes are dominated by π‐π interactions of the aromatic systems, which are substituted by strong hydrogen bonding interactions representing various structural motifs in the respective silanol structures.

New antenna ligand, 2-(phenylethynyl)-1,10-phenanthroline (PEP), and its luminescent Eu (III) complexes, Eu(PEP)₂Cl₃ and Eu(PEP)₂(NO₃)₃, are synthesized and characterized. The synthetic procedure applied is based on reacting of europium salts with ligand in hot acetonitrile solutions in molar ratio 1 to 2. The structure of the complexes is refined by X-ray diffraction based on the single crystals obtained. The compounds [Eu(PEP)₂Cl₃]·2CH₃CN and [Eu(PEP)₂(NO₃)₃]∙2CH₃CN crystalize in monoclinic space group P2_1/n and P2_1/c, respectively, with two acetonitrile solvent molecules. Intra- and inter-ligand π-π stacking interactions are present in solid stat and are realized between the phenanthroline moieties, as well as between the substituents and the phenanthroline units. The optical properties of the complexes are investigated in solid state, acetonitrile and dichloromethane solution. Both compounds exhibit bright red luminescence caused by the organic ligand acting as antenna for sensitization of Eu (III) emission. The newly designed complexes differ in counter ions in the inner coordination sphere, which allows exploring their influence on the stability, molecular and supramolecular structure, fluorescent properties and symmetry of the Eu (III) ion. In addition, molecular simulations are performed in order to explain the observed experimental behavior of the complexes. The discovered structure-properties relationships give insight on the role of the counter ions in the molecular design of new Eu (III) based luminescent materials.