Premelting Phenomena in <i>n</i>-Alcohols from Nonanol to Dodecanol

Pocheć, Michał; Niu, Hongyu; Ren, Liuchen; Bai, Shuhua; Orzechowski, Kazimierz

doi:10.1021/acs.jpcc.0c07417

Cited by 10 publications

(7 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The second change starts just below −18 • C (255 K) and is much bigger in magnitude, as expected for the surface premelting [25]. A large increase in the Piekara factor in close vicinity of the melting point was already observed [25,26] and was explained as a result of the Maxwell-Wagner effect, related to the formation of a liquid layer on the surface of solids [30]. The positive NDE effect, observed in larger distance from the melting point, needs more explanation.…”

Section: Experimental Data Analysissupporting

confidence: 65%

“…Therefore, the IR spectroscopy method was used to investigate the vibrational properties of n-octanol, with special emphasis on the OH stretching. The second experimental method, nonlinear dielectric effect (NDE), provides additional information on the premelting phenomena, especially as a macroscale processes, and has been proven by our previous findings to yield significant impact on the premelting analysis [25,26]. The main idea of this method is centered around the difference between low-and high-field dielectric permittivity, according to the following equation:…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Inside out Approach to Rotator State in Hydrogen-Bonded System—Experimental and Theoretical Cross-Examination in n-Octanol

Pocheć

Krupka

Panek

et al. 2022

IJMS

Self Cite

View full text Add to dashboard Cite

The experimental and theoretical description of premelting behavior is one of the most challenging tasks in contemporary material science. In this paper, n-octanol was studied using a multi-method approach to investigate it at macroscopic and molecular levels. The experimental infrared (IR) spectra were collected in the solid state and liquid phase at temperature range from −84 ∘C to −15 ∘C to detect temperature-related indicators of pretransitional phenomena. Next, the nonlinear dielectric effect (NDE) was measured at various temperatures (from −30 ∘C to −15 ∘C) to provide insight into macroscopic effects of premelting. As a result, a two-step mechanism of premelting in n-octanol was established based on experimental data. It was postulated that it consists of a rotator state formation followed by the surface premelting. In order to shed light onto molecular-level processes, classical molecular dynamics (MD) was performed to investigate the time evolution of the changes in metric parameters as a function of simulation temperature. The applied protocol enabled simulations in the solid state as well as in the liquid (the collapse of the ordered crystal structure). The exact molecular motions contributing to the rotator state formation were obtained, revealing an enabling of the rotational freedom of the terminal parts of the chains. The Car–Parrinello molecular dynamics (CPMD) was applied to support and interpret experimental spectroscopic findings. The vibrational properties of the stretching of OH within the intermolecular hydrogen bond were studied using Fourier transformation of the autocorrelation function of both dipole moments and atomic velocity. Finally, path integral molecular dynamics (PIMD) was carried out to analyze the quantum effect’s influence on the bridged proton position in the hydrogen bridge. On the basis of the combined experimental and theoretical conclusions, a novel mechanism of the bridged protons dynamics has been postulated—the interlamellar hydrogen bonding pattern, resulting in an additional OH stretching band, visible in the solid-state experimental IR spectra.

show abstract

Section: Experimental Data Analysissupporting

confidence: 65%

Section: Introductionmentioning

confidence: 99%

Inside out Approach to Rotator State in Hydrogen-Bonded System—Experimental and Theoretical Cross-Examination in n-Octanol

Pocheć

Krupka

Panek

et al. 2022

IJMS

Self Cite

View full text Add to dashboard Cite

show abstract

“…therein. They can be as follows [62,[75][76][77][78][79][80][81][82][83][84][85][86][87][88][89][90]: (i) premelting effects are 'weak' and rangelimited, (ii) they are detected only for some systems, (iii) they are detected for selected physical properties, (iv) there are no reports on their parameterization, except the very recent ref. [72], and (v) no solid-state pretransitional effects for freezing, i.e.…”

Section: Parametermentioning

confidence: 99%

Supercriticality, Glassy Dynamics, and the New Insight into Melting/Freezing Discontinuous Transition in Linseed Oil

Drozd-Rzoska,

Rzoska,

Łoś

2024

Biophysica

View full text Add to dashboard Cite

The long-range supercritical changes of dielectric constant, resembling ones observed in the isotropic liquid phase of liquid crystalline compounds, are evidenced for linseed oil—although in the given case, the phenomenon is associated with the liquid–solid melting/freezing discontinuous phase transitions. This ‘supercriticality’ can be an additional factor supporting the unique pro-health properties of linseed oil. Broadband dielectric spectroscopy studies also revealed the ‘glassy’ changes of relaxation times, well portrayed by the ‘activated and critical’ equation recently introduced. In the solid phase, the premelting effect characteristic for the canonic melting/freezing discontinuous transition, i.e., without any pretransitional effect in the liquid phase, has been detected. It is interpreted within the grain model, and its parameterization is possible using the Lipovsky model and the ‘reversed’ Mossotti catastrophe concept. For the premelting effect in the solid state, the singular ‘critical’ temperature correlates with the bulk discontinuous melting and freezing temperatures. Consequently, the report shows that linseed oil, despite its ‘natural and complex’ origins, can be considered a unique model system for two fundamental problems: (i) pretransitional (supercritical) effects in the liquid state associated with a weakly discontinuous phase transition, and (ii) the premelting behavior in the solid side of the discontinuous melting/freezing discontinuous transition.

show abstract

“…For the canonic case, no pretransitional effects are expected here [ 43 , 44 , 45 ]. Nevertheless, a set of results shows weak and range-limited pretransitional effects in the solid phase, which is not amenable to reliable parameterization [ 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ]. For this phenomenon, the transition from the liquid but partially ordered LC mesophase to the solid crystalline phase may be an important complementation, particularly when considering the supplementary impact of nanoparticles.…”

Section: Introductionmentioning

confidence: 99%

The Dominance of Pretransitional Effects in Liquid Crystal-Based Nanocolloids: Nematogenic 4-methoxybenzylidene-4′–butylaniline with Transverse Permanent Dipole Moment and BaTiO3 Nanoparticles

Drozd-Rzoska,

Łoś,

Rzoska

2024

Nanomaterials

View full text Add to dashboard Cite

The report presents static, low-frequency, and dynamic dielectric properties in the isotropic liquid, nematic, and solid phases of MBBA and related nanocolloids with paraelectric BaTiO3 nanoparticles (spherical, d = 50 nm). MBBA (4-methoxybenzylidene-4′–butylaniline) is a liquid crystalline compound with a permanent dipole moment transverse to the long molecular axis. The distortions-sensitive analysis of the dielectric constant revealed its hidden pretransitional anomaly, strongly influenced by the addition of nanoparticles. The evolution of the dielectric constant in the nematic phase shows the split into two regions, with the crossover coinciding with the standard melting temperature. The ‘universal’ exponential-type behavior of the low-frequency contribution to the real part of the dielectric permittivity is found. The critical-like pretransitional behavior in the solid phase is also evidenced. This is explained by linking the Lipovsky model to the Mossotti catastrophe concept under quasi-negative pressure conditions. The explicit preference for the ‘critical-like’ evolution of the apparent activation enthalpy is worth stressing for dynamics. Finally, the long-range, ‘critical-like’ behavior of the dissipation factor (D = tgδ), covering the isotropic liquid and nematic phases, is shown.

show abstract

Premelting Phenomena in n-Alcohols from Nonanol to Dodecanol

Cited by 10 publications

References 29 publications

Inside out Approach to Rotator State in Hydrogen-Bonded System—Experimental and Theoretical Cross-Examination in n-Octanol

Inside out Approach to Rotator State in Hydrogen-Bonded System—Experimental and Theoretical Cross-Examination in n-Octanol

Supercriticality, Glassy Dynamics, and the New Insight into Melting/Freezing Discontinuous Transition in Linseed Oil

The Dominance of Pretransitional Effects in Liquid Crystal-Based Nanocolloids: Nematogenic 4-methoxybenzylidene-4′–butylaniline with Transverse Permanent Dipole Moment and BaTiO3 Nanoparticles

Contact Info

Product

Resources

About