A5021253842- Liquid Crystal Research Advancements
- Material Dynamics and Properties
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Molecular spectroscopy and chirality
- Crystallography and molecular interactions
- Surfactants and Colloidal Systems
- Thermodynamic properties of mixtures
- Photochemistry and Electron Transfer Studies
- Chemical Thermodynamics and Molecular Structure
- Muon and positron interactions and applications
- Glass properties and applications
- NMR spectroscopy and applications
- Magnetism in coordination complexes
- Nonlinear Optical Materials Research
- Solid-state spectroscopy and crystallography
- Magnetic and transport properties of perovskites and related materials
- Analytical Chemistry and Chromatography
- Photochromic and Fluorescence Chemistry
- Lanthanide and Transition Metal Complexes
- Multiferroics and related materials
- Drug Solubulity and Delivery Systems
- Ferroelectric and Piezoelectric Materials
- Phase-change materials and chalcogenides
- Thermal and Kinetic Analysis
Institute of Nuclear Physics, Polish Academy of Sciences
2016-2025
Osaka University
2010-2025
Polish Academy of Sciences
2006-2021
Krakow Cardiovascular Research Institute
2019
Institute of Physics
2009
University of Tsukuba
2009
Jagiellonian University
2009
Joint Institute for Nuclear Research
2008
Novel drug delivery systems (DDSs) strive to eliminate or at least reduce the side effects and limitations associated with conventional medical products. Among many potential candidates for DDSs, there are one-dimensional micro- nanostructured materials such as electrospun fibers. In this study, two different polymers, i.e., amphiphilic block copolymer (poly(2-vinylpyridine-co-styrene)) hydrophobic polymer (polycaprolactone), were utilized base Through electrospinning coaxial techniques,...
Precisely controlled stoichiometric mixtures of Co(2+) and Fe(2+) metal ions were combined with the [W(V)(CN)8](3-) metalloligand in a methanolic solution to produce series trimetallic cyanido-bridged {Fe(9-x)Co(x)[W(CN)8]6(MeOH)24}·12MeOH (x = 0, 1, ..., 8, 9; compounds 9) clusters. All compounds, 0-9, are isostructural, consist pentadecanuclear clusters six-capped body-centered cube topology, capped by methanol molecules which coordinated 3d centers. Thus, they can be considered as unique...
A bimetallic pentadecanuclear cyanido-bridged {Fe9[W(CN)8]6 (MeOH)24}·xMeOH cluster of an FeII/III–WIV/V mixed valence nature, reveals a reversible single-crystal-to-single-crystal transformation, concomitant with metal-to-metal charge transfer between Fe and W ions. The dominance HSFeII–NC–WV units at high temperature, HSFeIII–NC–WIV low leads to unprecedented reversed thermal hysteresis loop in magnetic measurements.
Vitrification of the antiferroelectric smectic-C_{A}^{*} phase is reported for orthoconic mixture W-1000 and its new derivative W-356. The crystallization not observed even upon slow cooling cold on subsequent heating also absent. Molecular dynamics in smectic phases both mixtures investigated down to 173 K fragility parameters are determined from temperature behavior α-process. X-ray diffraction applied compare structural W-356 as well study changes during glass transition Sm-C_{A}^{*}...
Features of glass transition in liquid crystalline nematic and smectic E, B IA phases selected materials observed by means the polarising microscopy Fourier transform infrared spectroscopy (FTIR) are reported. Evolution cracking a coincidence its disappearance temperature with (Tg) on heating is shown discussed context processes that occur glass. The shape dependencies absorption bands as signature transition.
The kinetics of the non-isothermal and isothermal crystallization crystalline smectic B phase (soft crystal B, SmBcr) in 4-n-butyloxybenzylidene-4′-n′-octylaniline (BBOA) was studied by a combination differential scanning calorimetry (DSC), broadband dielectric spectroscopy (BDS) polarized optical microscopy (POM). On cooling, part SmBcr undergoes conversion to remainder forms glassy state; after glass softens, is completed during subsequent heating. By analyzing area growing texture as...
This publication presents methods of distinguishing the focal texture conical smectic phase A (SmA) and crystalline B (CrB). Most often, characteristic transition bars are observed in polarized light at temperature point SmA–CrB transition. TOApy software transforms each image from a series images recorded during POM observation to function intensity versus temperature. Thermo-optical analysis is powerful quantitative tool notice this transition, but it has some limitations. The other...
Three liquid crystalline equimolar mixtures are formulated, each containing the MHPOBC compound and homolog from 3FmHPhF6 series with m = 4, 5 or 6. The properties of investigated by differential scanning calorimetry, polarizing optical microscopy, X-ray diffraction, electro-optic measurements, UV-Vis-NIR dielectric spectroscopies. In all mixtures, smectic A*, C*, C$_A$* phases observed. Each mixture can be supercooled forms glass at 225-238 K. transition temperature decreases increasing...
The phase behavior of three liquid crystal derivatives 4-pentyl-4″-propyl-1,1′:4′,1″-terphenyls differing in number fluorine atoms the mesogenic core has been described. Calorimetric and microscopic studies show that fluoro-substitution rigid affects whether a given undergoes crystallization or glass transition during cooling. Compounds with highest crystallize, while other vitrify from conformationally disordered phase. different mechanisms cold processes. Dielectric measurements uncover...
The unique enantiopure {[Λ-Co(II)((R)-mpm)2]3[W(V)(CN)8]2}·9H2O [(R)-1] and {[Δ-Co(II)((S)-mpm)2]3[W(V)(CN)8]2}·9H2O [(S)-1], where mpm = α-methylpyridinemethanol, magnetic spongelike materials, crystallizing in the chiral P21 space group, are constructed of cyanido-bridged {Co3W2} trigonal bipyramids with three cis-[Co(II)(mpm)2(μ-NC)2] moieties equatorial sites two [W(V)(CN)8](3-) units apical positions. arrangement clusters crystal lattice is controlled by interactions crystallization H2O...
The relaxation dynamics in the thermodynamic states of a glass-forming liquid crystal was studied. role inter- and intramolecular interactions ester groups during vitrification process revealed.
This paper describes the insight into different nature of cold- and melt crystallization kinetics a smectogenic liquid crystal.
The results of mid-infrared spectroscopy and X-ray studies the third member 4-n-alkyl-4'-isothiocyanatobiphenyl (nTCB) homologous series are presented. Correspondence between phase transitions observed by means IR those given adiabatic calorimetry was found. structure five solid phases obtained measurements. spectroscopic data give arguments supporting identification glass smectic E phase. Assignment vibrational bands, in E, one crystalline phases, with help hybrid B3LYP/6-311++G(d,f)...
The results of dielectric relaxation spectroscopy and polarizing microscope observation the 4′-butyl-4-(2-methylbutoxy)azoxybenzene (abbreviated as 4ABO5*) are presented. Numerical analysis spectra points to complex dynamics 4ABO5* molecules in isotropic, cholesteric, crystalline phases. Two well-separated maxima on imaginary part permittivity third low frequency process, hidden conductivity region, were detected described cholesteric Temperature dependence mean times characterizing...
This article presents the crystallization behavior and molecular dynamics of supercooled nematic state newly synthesized liquid crystal 2,7-bis(4-pentylphenyl)-9,9-diethyl-9H-fluorene (5P-EtFLEt-P5) studied by means broadband dielectric spectroscopy (BDS). 5P-EtFLEt-P5 is a fragile glass-forming system with high fragility parameter (mf ≈ 121). The study compares isothermal melt- cold-crystallization processes at several selected temperatures Tc in vicinity glass-transition temperature Tg...
Vibrational dynamics in the glass transition and cold crystallization process of (S)-4′-(1-methyloctyloxycarbonyl) biphenyl-4-yl 4-[7-(2,2,3,3,4,4,4-heptafluorobutoxy) heptyl-1-oxy]-benzoate (3F7HPhH7) was studied by Fourier transform infrared spectroscopy (FTIR) during cooling/heating experimental runs. The measured spectra processing supported quantum chemical density functional theory (DFT) calculations (frequency assignments). perturbation-correlation moving window two-dimensional...
Glass transition of the antiferroelectric hexatic smectic phase is reported for 3F5HPhH6 compound. The relationship between cold crystallization kinetics and molecular dynamics determined.
The molecular dynamics of 4-n-butyloxybenzylidene-4'-n'-octylaniline (BBOA, abbreviated also as 4O.8) was studied by broadband dielectric spectroscopy (BDS) for samples that were exposed to various thermal treatments. Phase transitions between liquid crystalline phases (N, SmA, SmBhex, and SmBCr) evidenced abrupt changes in the temperature dependence permittivity spectra relaxation times. A particularly complex dynamic behavior revealed highly ordered SmBCr phase showed clear evidence...
A Siamese neural network, a deep learning technique, was utilized to distinguish selected liquid crystal phases (antiferroelectric smectic C *, I, and G) from their corresponding glasses.