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The advancement of ultra-sensitive optical manometers is crucial for exploring the behavior of materials under extreme conditions. Herein, we introduce a novel rare-earth complex Eu(bpyO2)4(PF6)3 as a promising candidate for high-precision pressure sensing, addressing the gap in sensitivity of existing luminescence manometers below 1 GPa. Through comprehensive high-pressure spectroscopic and single-crystal X-ray diffraction studies, we have found a phase transition in Eu(bpyO2)4(PF6)3 at 1.25 GPa, where the ambient pressure phase α (space group Pbcn) transforms to the high-pressure phase β (space group P21/n). This process reduces the contribution of intramolecular anagostic bonds complementing the coordination sphere modifying the observed emission spectra, underpinning the role of crystal engineering in the development of dual-mode (ratiometric and lifetime-based) luminescence manometers. The ratiometric mode, measuring the intensity ratio between two emission bands of Eu3+ ions, demonstrates a remarkable relative sensitivity, exceeding 120.7% GPa−1 at approximately 1.6 GPa. The lifetime-based mode utilizes pressure-influenced luminescence kinetics and shows a maximal relative sensitivity of 55.1% GPa−1, classifying it as the most sensitive optical manometer operating in this mode. The unique bimodal readouts and unparalleled sensitivity of Eu(bpyO2)4(PF6)3 across both modes represent a significant advancement in pressure sensing technologies. [ABSTRACT FROM AUTHOR]

New bismuth (III) complexes with acetophenone-4-methyl-3-thiosemicarbazone (L) and halogens (Cl and Br) in both bridging and terminal positions have been synthesized and structurally characterized using single-crystal X-ray diffraction. The pure complexes (Cl or Br) were found to be highly isostructural, which motivated our attempts to create solid solutions of these complexes. A series of such compounds was prepared using various procedures and stoichiometries. A method for determining the mutual concentrations of different halogens, based on the positions of selected peaks in powder diffraction patterns, was tested and compared with other methods. [ABSTRACT FROM AUTHOR]

The antiproliferative and antibacterial activities of thiosemicarbazones increase markedly with the presence of metal ions. One of the factors determining the activity of metal thiosemicarbazone complexes is the coordination structure. In this study, the biological effects of new antimony (III) and bismuth (III) thiosemicarbazone complexes with different binding modes and geometrical structures were demonstrated. Three new complexes, with the formulae {[SbCl3(µ2-S-Hacptsc)(η1-S-Hacptsc)], 2/3H2O,1/3CH2Cl2}, {[SbCl3(κ2-S,N-Hacpmtsc)(η1-S-Hacpmtsc)2CH2Cl2]}, and{[BiCl3(η1-S-Hbzmtsc)3]·C2H5OH}, where Hacptsc: acetophenone thiosemicarbazone, Hacpmtsc: acetophenone-N-methyl thiosemicarbazone, Hbzmtsc: benzaldehyde-N-methyl thiosemicarbazone) were elucidated by different methods and deeply analyzed in accordance with their structure by X-ray structure analysis and Atoms-In-Molecules topological analysis. This analysis provided a deeper understanding of the coordination spheres of the Sb/Bi complexes. For instance, the first reported two binding modes of the same ligand are observed in a single crystal structure of antimony (III) halide complexes. Additionally, in one of the complexes, a solid-to-solid phase transition was detected and analyzed in detail. Those complexes, very unique in terms of their geometry, have also been tested for their in vitro cytotoxic activity against human adenocarcinoma cervical cancer (HeLa) cells, whereas antimony (III) complex 1is the most active complex of this study. Further, the antibacterial activity of the complexes has been screened against two Gram-negative (Pseudomonas aeruginosa and Escherichia coli) and two Gram-positive (Staphylococcus epidermidis and Staphylococcus aureus) pathogenic bacteria. From the results, it is found that all the complexes exhibited significant activity against the Gram-negative pathogenic bacteria. [ABSTRACT FROM AUTHOR]