scholarly journals A DFT/PCM Study on the Affinity of Salinomycin to Bind Monovalent Metal Cations

Molecules ◽  
2022 ◽  
Vol 27 (2) ◽  
pp. 532
Author(s):  
Todor Dudev ◽  
Diana Cheshmedzhieva ◽  
Peter Dorkov ◽  
Ivayla Pantcheva
Keyword(s):  
Free Energy ◽  
Dielectric Properties ◽  
Ionic Radius ◽  
Metal Cations ◽  
Coordination Numbers ◽  
Monovalent Metal ◽  
Sphere Geometry ◽  
High Dielectric ◽  
Water Ligands ◽  
Dielectric Environment

The affinity of the polyether ionophore salinomycin to bind IA/IB metal ions was accessed using the Gibbs free energy of the competition reaction between SalNa (taken as a reference) and its rival ions: [M+-solution] + [SalNa] → [SalM] + [Na+-solution] (M = Li, K, Rb, Cs, Cu, Ag, Au). The DFT/PCM computations revealed that the ionic radius, charge density and accepting ability of the competing metal cations, as well as the dielectric properties of the solvent, have an influence upon the selectivity of salinomycin. The optimized structures of the monovalent metal complexes demonstrate the flexibility of the ionophore, allowing the coordination of one or two water ligands in SalM-W1 and SalM-W2, respectively. The metal cations are responsible for the inner coordination sphere geometry, with coordination numbers spread between 2 (Au+), 4 (Li+ and Cu+), 5/6 (Na+, K+, Ag+), 6/7 (Rb+) and 7/8 (Cs+). The metals’ affinity to salinomycin in low-polarity media follows the order of Li+ > Cu+ > Na+ > K+ > Au+ > Ag+ > Rb+ > Cs+, whereas some derangement takes place in high-dielectric environment: Li+ ≥ Na+ > K+ > Cu+ > Au+ > Ag+ > Rb+ > Cs+.

scholarly journals Effect of Average Ionic Radius of A-site, B-site in Ba0.85X0.15TiO3, BaY0.15Ti 0.85O3 Systems Respectively (X = Pb, Ca, Co), (Y = Zr, Mn, Si) as a Perovskite Structure Ceramics (ABO3) on Crystal Structure, Curie Temperature

2021 ◽  
Author(s):  
Jasim Yaseen
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Barium Titanate ◽  
Curie Temperature ◽  
Ionic Radius ◽  
Structural Parameters ◽  
Solid State Reaction Method ◽  
Average Ionic Radius ◽  
High Dielectric ◽  
A Site

Abstract Barium titanate BaTiO3 is one of the most ferroelectrics. Its commonly used in capacitors due to its high dielectric constant. In this study, our goal is to determine the extent to which the change in the average ionic radius of A, B sites affects the structural, dielectric properties of this ceramic. In this study, barium titanate (Ba0.85X0.15TiO3, BaY0.15Ti0.85O3) (X = Pb, Ca, Co, Y= Zr, Si, Mn) was prepared by solid state reaction method in which the calcination temperature was 1200 °C for 2 hours. Structural characterization and dielectric properties were determined and calculated by using x-ray diffractometer, RCL-Meter (PM6303) at frequency 20 Hz using different temperature respectively. The results of the work showed that the average ionic radius at the A, B sites plays a large and clear role in determining the values of the dielectric constant and Curie temperature in perovskites in addition to the structural parameters.

High dielectric properties, TiO2 nanoparticles doped PDLC devices for lower switching voltage

2021 ◽  
pp. 1-10
Author(s):  
Miaomiao Jia ◽  
Yuzhen Zhao ◽  
Hong Gao ◽  
Dong Wang ◽  
Zongcheng Miao ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Tio2 Nanoparticles ◽  
Switching Voltage ◽  
High Dielectric

New Perovskite Nanomaterials and Their Integrations into High-k Dielectrics

2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000072-000077
Author(s):  
Minoru Osada ◽  
Takayoshi Sasaki
Keyword(s):  
Dielectric Properties ◽  
Room Temperature ◽  
Bottom Electrode ◽  
Dielectric Constants ◽  
Dielectric Films ◽  
Layered Perovskite ◽  
Layer By Layer ◽  
High K ◽  
High K Dielectric ◽  
High Dielectric

We report on a bottom-up manufacturing for high-k dielectric films using a novel nanomaterial, namely, a perovskite nanosheet (LaNb2O7) derived from a layered perovskite by exfoliation. Solution-based layer-by-layer assembly of perovskite nanosheets is effective for room-temperature fabrication of high-k nanocapacitors, which are directly assembled on a SrRuO3 bottom electrode with an atomically sharp interface. These nanocapacitors exhibit high dielectric constants (k > 50) for thickness down to 5 nm while eliminating problems resulting from the size effect. We also investigate dielectric properties of perovskite nanosheets with different compositions (LaNb2O7, La0.95Eu0.05Nb2O7, and Eu0.56Ta2O7) in order to study the influence of A- and B-site modifications on dielectric properties.

Structure instability-induced high dielectric properties in [001]-oriented 0.68Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 crystals

2019 ◽  
Vol 28 (5) ◽  
pp. 057701
Author(s):  
Xiao-Juan Li ◽  
Xing Fan ◽  
Zeng-Zhe Xi ◽  
Peng Liu ◽  
Wei Long ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
High Dielectric

scholarly journals Fabrication of High Permittivity Resin Composite for Vat Photopolymerization 3D Printing: Morphology, Thermal, Dynamic Mechanical and Dielectric Properties

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3818 ◽  
Author(s):  
Malas ◽  
Isakov ◽  
Couling ◽  
Gibbons
Keyword(s):  
Dielectric Properties ◽  
3D Printing ◽  
Resin Composite ◽  
Ceramic Powder ◽  
Reactive Polymer ◽  
Calcium Copper Titanate ◽  
Double Function ◽  
High Dielectric ◽  
Powder Content ◽  
5 Ghz

The formulation of a high dielectric permittivity ceramic/polymer composite feedstock for daylight vat photopolymerization 3D printing (3DP) is demonstrated, targeting 3DP of devices for microwave and THz applications. The precursor is composed of a commercial visible light photo-reactive polymer (VIS-curable photopolymer) and dispersed titanium dioxide (TiO2, TO) ceramic nano-powder or calcium copper titanate (CCT) micro-powder. To provide consistent 3DP processing from the formulated feedstocks, the carefully chosen dispersant performed the double function of adjusting the overall viscosity of the photopolymer and provided good matrix-to-filler bonding. Depending on the ceramic powder content, the optimal viscosities for reproducible 3DP with resolution better than 100 µm were η(TO) = 1.20 ± 0.02 Pa.s and η (CCT) = 0.72 ± 0.05 Pa.s for 20% w/v TO/resin and 20% w/v CCT/resin composites at 0.1 s−1 respectively, thus showing a significant dependence of the “printability” on the dispersed particle sizes. The complex dielectric properties of the as-3D printed samples from pure commercial photopolymer and the bespoke ceramic/photopolymer mixes are investigated at 2.5 GHz, 5 GHz, and in the 12–18 GHz frequency range. The results show that the addition of 20% w/v of TO and CCT ceramic powder to the initial photopolymer increased the real part of the permittivity of the 3DP composites from ε’ = 2.7 ± 0.02 to ε’(TO) = 3.88 ± 0.02 and ε’(CCT) = 3.5 ± 0.02 respectively. The present work can be used as a guideline for high-resolution 3DP of structures possessing high-ε.

Sign in / Sign up

Export Citation Format

Share Document