Ferrous tainiolite, Cs[Fe2Li]
o
[Si4]
t
O10F2, has been synthesized from the melt in gastight molybdenum
crucibles. The electric conductivity has been measured by impedance spectroscopy. As compared to
natural micas, which are insulators, good conductivity is observed. The layered silicate can be further
modified by ion exchange, which makes it a promising host structure for sensor materials. The estimated
activation energy is as low as 0.79 eV. Upon Ba2+ exchange for Cs+, structural Fe2+ is partially oxidized
(33%), and the layer charge is reduced significantly, resulting in a coarse-grained but swollen (monolayer
hydrate) smectite-type layered silicate. Therefore, further functionalization by pillaring will be feasible
resulting in a conducting microporous material. The new material has been characterized by the analysis
of chemical composition (wavelength dispersive X-ray spectroscopy and laser ablation-inductively coupled
plasma−mass spectrometry), differential thermal analysis, electron microscopy, Mössbauer, UV−vis/NIR, impedance spectroscopy, and single-crystal structure refinement (wR(F
2) = 0.0883). The structure
is of the 1M polytype (C2/m) with cell parameters a = 5.277(2) Å, b = 9.148(2) Å, c = 10.804(2) Å,
and β = 99.19(3)°. The congruent melting point was observed at 1103 (±5) K.
We found that the chokeberry and elderberry extracts rich in cyanidin glycosides possess better antioxidant and anticytotoxic activities in comparison to blueberry or bilberry extracts with complex anthocyanin profiles.
In the present article, we reported the application of the extract of leaves from Solidago canadensis L. for the green synthesis of triangular and hexagonal gold nanoparticles (AuNPs). The phytochemical characterization, by reaction with HAuCl 4 solutions, showed that the extract of Solidago canadensis L. contained the secondary metabolites that can act both as reducing and as stabilizing agents. For the synthesis of AuNPs, the effects of the HAuCl 4 concentration (0.25-0.975 mM) and the reaction time (10-180 min) were investigated. The formation of AuNPs is confirmed by the color change from yellowish to purple-red. Photoluminescence measurements of Au nanocolloids showed a continuous emission band ranging from violet to red. UV-Vis characterization of AuNPs in the prepared nanocolloids showed surface plasmon resonance peaks at 530 and > 870 nm. TEM revealed that the AuNPs are in the range of 8-200 nm, they have spherical, triangular, and hexagonal forms of varying sizes. AFM and STM showed a non-ideal relief of large triangular and hexagonal gold nanoprisms. The EDX analysis, XRD and SAED patterns confirmed the face-center cubic structure of AuNPs.
A few different theoretical methods for assigning the partial atomic charges were benchmarked for calculation of the hydrophilic/lipophilic index (HLI). The coefficients were selected to produce the best correlation of the HLI values with the experimental octanol-water partition. Different parameters were checked in calculations of partial charges to get the best performance of the HLI values obtained. Thus, four partitioning schemes (Coulson, Mulliken, Merz-Kollman, Ford-Wang) were benchmarked for calculations of atomic charges with six semiempirical methods (AM1, PM3, RM1, PM6, PM6-D3H4, PM7). Moreover, five distinct types of partial atomic charges (Mulliken, Hirshfeld, Löwdin, CHELPG, NPA), obtained at the Hartree-Fock and DFT levels of theory with three basis sets, were tested for their ability to produce the HLI values with the best correlation to experimental logP coefficients of 50 mono-charged organic anions. In the case of the semiempirical methods, the best correlation between the HLI and logP values (the correlation coefficient r = 0.9216) was obtained with the AM1 Ford-Wang parametric electrostatic potential charges. The Mulliken and Coulson charges calculated with the PM7 method can be used as an alternative to AM1, with the r values of 0.9107 and 0.8984, respectively. In the case of the DFT, the PBE/def2-TZVP natural population analysis charges produce the best correlation (r = 0.9220). Nevertheless, in spite of a marginally lower performance (r = 0.9159), the NPA charges computed at the PBE/def2-SVP level are more robust and can be regarded as the optimum choice for calculating the HLI values. Graphical abstract The hydrophilic/lipophilic index (HLI).
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