[en] The absorption, excitation, photostimulation spectra and thermoluminescence creation spectra of pure BaFX (X=Br, Cl) and BaFX:Eu²⁺ single crystals were studied in the vacuum ultraviolet region 5-10 eV at temperatures 6-300 K. The creation of a V_k-related thermoluminescence peak was observed when the BaFX : Eu²⁺ crystal was illuminated with vacuum ultraviolet (VUV) photons with energy above 6 eV. Band-to-band transitions begin above 8-9 eV. Low temperature photostimulation spectra for Eu²⁺ luminescence created by 6-7 eV photons showed new bands in the infrared region, the intensities of which were directly proportional to the Eu²⁺ concentration. However, the same infrared photostimulation bands for exciton luminescence were observed also in undoped crystals after X-ray irradiation. The results show that trapped electrons and self-trapped holes were created by VUV photons in BaFX:Eu²⁺ crystals. It was concluded that Eu²⁺ ions assist in creation of free electrons and holes by photons with energy 2-3 eV lower than those of band-to-band transitions

[en] When the accuracy of the measurements is known, the convention is used that the figures following the ± sign have the same power of ten as does the last significant figure of the reported quantity (i.e. 4.3772 ± 2 should be read as 4.3772 ± 0.0002). (author)

No abstract available

[en] When the accuracy of the measurements is known, the convention is used that the figures following the ± sign have the same power of ten as does the last significant figure of the reported quantity (i.e. 4.3 7 72 ± 2 should be read as 4.3772 ± 0.0002).

[en] Two main methods of separation using the distillation method are given and evaluated, namely evaporation and distillation in carrier gas flow. Two basic apparatus are described for illustrating the methods used. The use of the distillation method in radiochemistry is documented by a number of examples of the separation of elements in elemental state, volatile halogenides and oxides. Tables give a survey of distillation methods used for the separation of the individual elements and give conditions under which this separation takes place. The suitability of the use of distillation methods in radiochemistry is discussed with regard to other separation methods. (L.K.)

[en] 1.3-dimethyl-2-imidazolidinone (dimethylethyleneurea - DMEU), a relatively new non-aqueous solvent of high polarity, was used as ligand in the preparation of nine coordination compounds with some zinc group halides. The compounds were characterized by elemental analysis, IR TGA, DTA and DSC. The metal-oxggen bond enthalpies were estimated, as well another thermochemical parameters. (author)

[en] Inorganic cesium lead halide perovskites offer a pathway towards thermally stable photovoltaics. However, moisture-induced phase degradation restricts the application of hole transport layers (HTLs) with hygroscopic dopants. Dopant-free HTLs fail to realize efficient photovoltaics due to severe electrical loss. Herein, we developed an electrical loss management strategy by manipulating poly(3-hexylthiophene) with a small molecule, i.e., SMe-TATPyr. The developed P3HT/SMe-TATPyr HTL shows a three-time increase of carrier mobility owing to breaking the long-range ordering of "edge-on'' P3HT and inducing the formation of "face-on'' clusters, over 50 % decrease of the perovskite surface defect density, and a reduced voltage loss at the perovskite/HTL interface because of favorable energy level alignment. The CsPbI${}_2$Br perovskite solar cell demonstrates a record-high efficiency of 16.93 % for dopant-free HTL, and superior moisture and thermal stability by maintaining 96 % efficiency at low-humidity condition (10-25 % R. H.) for 1500 hours and over 95 % efficiency after annealing at 85 °C for 1000 hours. (© 2021 Wiley‐VCH GmbH)

[en] A noble phenylsulfonyl reagent 8 having α-oxo (cyanomethylene)triphenylphosphorane ylide subunit readily condensed with various alkyl halides under basic conditions to afford β-alkyl-α-oxo-β-phenylsulfonyl (cyanomethylene)triphenylphosphorane ylides 9 in excellent yields. These sulfonyl ylides 9 were then reductively desulfonylated with Na(Hg)/Na₂HPO₄ in the presence of methanol to provide α-keto (cyanomethylene)-triphenylphosphorane ylides 2' in good to excellent yields. Our new synthetic approach offers an expeditious access to various α-keto (cyanomethylene)triphenylphosphorane ylides from alkyl halides utilizing a new phenylsulfonyl reagent as the key reagent under mild reaction conditions in good overall yields

[en] The local coordination structures around the doping Yb²⁺ ions in sodium and potassium halides were calculated by using the first-principles supercell model. Both the cases with and without the charge compensation vacancy in the local environment of the doping Yb²⁺ were calculated to study the effect of the doping on the local coordination structures of Yb²⁺. Using the calculated local structures, we obtained the crystal-field parameters for the Yb²⁺ ions doped in sodium and potassium halides by a method based on the combination of the quantum-chemical calculations and the effective Hamiltonian method. The calculated crystal-field parameters were analyzed and compared with the fitted results. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

[en] A one-pot efficient procedure for the synthesis of 2,4,5-triaryl-1H-imidazole derivatives in good to excellent yields by reaction between hexamethyldisilazane and arylaldehydes, benzyl alcohols, benzyl halides in the presence of molecular iodine has been developed. The remarkable advantages of this method are the simple workup procedure, high yields of products, and the availability of reagents