Sylwester J. Rzoska

Bio: Sylwester J. Rzoska is an academic researcher from Polish Academy of Sciences. The author has contributed to research in topics: Dielectric & Liquid crystal. The author has an hindex of 33, co-authored 216 publications receiving 3570 citations. Previous affiliations of Sylwester J. Rzoska include University of Silesia in Katowice & Silesian University.

Impact of Pressure on Low-Molecular Weight Near-Critical Mixtures of Limited Miscibility.

Abstract: Near-critical mixtures of limited miscibility are significant for chemical physics, soft matter physics, and a variety of challenging applications. Their basic properties can be tuned by compressin...

Time-scale dependence of the critical exponent for the nonlinear dielectric effect in a critical binary solution

Abstract: Low frequency [(300 kHz) results for the nonlinear dielectric effect (NDE)] (variation in electric permittivity of liquids induced by a strong, steady electric field) in a critical, binary solution have been obtained. Their comparison with NDE measurements for 9 and 6 MHz indicate that the appearance of a mean-field region near the critical consolute temperature (${\mathit{T}}_{\mathit{C}}$) and the crossover to the nonclassical behavior remote from ${\mathit{T}}_{\mathit{C}}$ could be associated not only with the degree of elongation of critical fluctuations but also with the time scale involved. This behavior is possibly due to the correlation between the relaxation time of critical fluctuations and the measurement frequency. The result obtained supplements the analysis given in Phys. Rev. E 48, 1136 (1993) plus Phys. Rev. E 47, 1445 (1993) and Phys. Rev. E 50, 5234 (1994) of the behavior near a critical consolute point of two effects immanently associated with the application of a strong, steady electric field: the electro-optical Kerr effect and nonlinear dielectric effect. (c) 1995 The American Physical Society

An isothermic coexistence curve in the nitrobenzene–decane–benzene solution

Abstract: An isothermic coexistence curve in the nitrobenzene–decane–benzene solution has been determined. Its shape can be described by the single, power relation with the exponent β’=0.376±0.008. This result is consistent, within the limits of error, with theoretical predictions based on the Fisher’s renormalization.

Dynamics and Pretransitional Effects in C60 Fullerene Nanoparticles and Liquid Crystalline Dodecylcyanobiphenyl (12CB) Hybrid System

Abstract: The report shows the strong impact of fullerene C60 nanoparticles on phase transitions and complex dynamics of rod-like liquid crystal dodecylcyanobiphenyl (12CB), within the limit of small concentrations. Studies were carried out using broadband dielectric spectroscopy (BDS) via the analysis of temperature dependences of the dielectric constant, the maximum of the primary loss curve, and relaxation times. They revealed a strong impact of nanoparticles, leading to a ~20% change of dielectric constant even at x = 0.05% of C60 fullerene. The application of the derivative-based and distortion-sensitive analysis showed that pretransitional effects dominate in the isotropic liquid phase up to 65 K above the clearing temperature and in the whole Smectic A mesophase. The impact of nanoparticles on the pretransitional anomaly appearance is notable for the smectic–solid phase transition. The fragility-based analysis of relaxation times revealed the universal pattern of its temperature changes, associated with scaling via the “mixed” (“activated” and “critical”) relation. Phase behavior and dynamics of tested systems are discussed within the extended Landau–de Gennes–Ginzburg mesoscopic approach.

Classification of secondary relaxation in glass-formers based on dynamic properties.

Abstract: Dynamic properties, derived from dielectric relaxation spectra of glass-formers at variable temperature and pressure, are used to characterize and classify any resolved or unresolved secondary relaxation based on their different behaviors. The dynamic properties of the secondary relaxation used include: (1) the pressure and temperature dependences; (2) the separation between its relaxation time τβ and the primary relaxation time τα at any chosen τα; (3) whether τβ is approximately equal to the independent (primitive) relaxation time τ0 of the coupling model; (4) whether both τβ and τ0 have the same pressure and temperature dependences; (5) whether it is responsible for the “excess wing” of the primary relaxation observed in some glass-formers; (6) how the excess wing changes on aging, blending with another miscible glass-former, or increasing the molecular weight of the glass-former; (7) the change of temperature dependence of its dielectric strength Δeβ and τβ across the glass transition temperature Tg; ...

Supercooled dynamics of glass-forming liquids and polymers under hydrostatic pressure

Abstract: An intriguing problem in condensed matter physics is understanding the glass transition, in particular the dynamics in the equilibrium liquid close to vitrification Recent advances have been made by using hydrostatic pressure as an experimental variable These results are reviewed, with an emphasis in the insight provided into the mechanisms underlying the relaxation properties of glass-forming liquids and polymers