A detailed investigation of the phase diagram 1-butyl-3-methyl imidazolium hexafluorophosphate ([bmim][PF(6)]) is presented on basis a wide set experimental data accessing thermodynamic, structural, and dynamical properties this important room temperature ionic liquid (RTIL). The combination quasi adiabatic, continuous calorimetry, angle neutron X-ray diffraction, elastic scattering allows exploration many novel features material. Thermodynamic microscopic structural information derived both...

Raman spectra in superionic glasses ${(\mathrm{AgI})}_{x}{({\mathrm{Ag}}_{2}\mathrm{O}\ifmmode\cdot\else\textperiodcentered\fi{}n{\mathrm{B}}_{2}{\mathrm{O}}_{3})}_{1\ensuremath{-}x}$ for various values of $x$ ($0.1\ensuremath{\le}x\ensuremath{\le}0.55$) and $n (2\ensuremath{\le}n\ensuremath{\le}4)$ are reported. For comparison we also studied binary (${\mathrm{Ag}}_{2}\mathrm{O}\ifmmode\cdot\else\textperiodcentered\fi{}n{\mathrm{B}}_{2}{\mathrm{O}}_{3}$). They provide light scattering...

An ultrasonic study of the loss characteristics and sound velocity was carried out in AgI-${\mathrm{Ag}}_{2}$O-${\mathrm{B}}_{2}$${\mathrm{O}}_{3}$ glasses as a function temperature silver-compound concentration. From behavior ${({\mathrm{Ag}}_{2}\mathrm{O})}_{y}{({\mathrm{B}}_{2}{\mathrm{O}}_{3})}_{1\ensuremath{-}y}$, formation fourfold-coordinated boron ions is suggested. This increases rapidly, $y$, until $y\ensuremath{\simeq}0.25$; for larger strong production singly bonded oxygen...

The dynamics of ethylcyclohexane are investigated by high resolution dielectric spectroscopy aiming to characterize the relevant relaxational features this simple system in its fluid, supercooled liquid, and glassy states. signature structural relaxation is a primary loss peak with amplitude Δε=0.01, secondary process found state. This β compared “slow” revealed ultrasonics previously γ χ processes similar materials containing cyclohexyl group. results suggest that an intramolecular mode...

The system $(\mathrm{AgI}{)}_{1\ensuremath{-}x}({\mathrm{Ag}}_{2}{\mathrm{MoO}}_{4}{)}_{x}$ is studied with ${}^{109}\mathrm{Ag}$ solid-state NMR and differential scanning calorimetry. Glasses are formed for $0.2<x<0.4.$ Outside the glass formation region a glassy phase of molar composition ${0.66\mathrm{}\mathrm{A}\mathrm{g}\mathrm{I}\ensuremath{-}0.33\mathrm{}\mathrm{Ag}}_{2}{\mathrm{MoO}}_{4}$ always found, which accompanied by \ensuremath{\beta}-AgI or...

The glass-former m-toluidine displays the characteristic properties of a fragile supercooled liquid, which suggest existence slow secondary relaxation process. In view recently realized importance such feature, we have conducted dielectric search for process in viscous and glassy m-toluidine. Based on high-resolution experiments distilled can be identified has typical Johari-Goldstein beta relaxation. As result, previous hypothesis that methyl group might responsible suppressing dynamics no...

Wide band dielectric spectroscopy has been used to study the bulk dynamics of simple supercooled liquid m-toluidine. Following temperature and frequency dependence response we find a stretched relaxation process, stretching parameter which is dependent. The observed decoupling between rotational translational diffusion parameters at low temperatures may be result heterogeneous dynamics.

We have measured, as a function of temperature and frequency, the velocity attenuation sound down to glass transition fragile glass-forming molecular liquid m-toluidine. The mechanical relaxation process is compared with dielectric one recently studied on same substance. Arrhenius plot log(τ) vs 1/T shows that time associated ultrasonic measurements previously found by spectroscopy in region.

The specific heat of some alkyl-cyclohexanes in their liquid, supercooled crystalline, and (for the first time) glassy states has been measured by quasiadiabatic calorimetry. Thermodynamic properties as well glass forming ability have studied a function systematic changes molecular structure. Only one stable crystalline phase is observed experimentally for ethylcyclohexane, propylcyclohexane, butylcyclohexane. In case methylcyclohexane, experimental evidence provided crystal-to-crystal...

An experimental study of the sound velocity in AgI-${\mathrm{Ag}}_{2}$O-${\mathrm{B}}_{2}$${\mathrm{O}}_{3}$ superionic glassy systems is presented. Measurements were performed at 5 MHz and (77--450)-K temperature range as a function AgI concentration. The ultrasonic behavior explained terms two physical contributions: first due to thermally activated relaxation processes; second one, anharmonic effects. Moreover, analysis room-temperature elastic moduli, increasing concentrations AgI, seems...

Abstract The main relaxation observed in supercooled ethylcyclohexane the 50 Hz–20 kHz frequency range using high-resolution dielectric spectroscopy displays an unusual pattern. slope of loss profile above peak frequency, progressively tends to zero with increasing temperature. features could be compatible existence different underlying processes. A simple approach based on scaling is exploited provide relevant information properties primary and secondary ethylcyclohexane. apparently...

Dynamics of supercooled m-toluidine close to the glass transition have been investigated by dynamic shear modulus measurements and stress relaxation experiments. The viscoelastic response this material follows time-temperature-superposition in temperature range investigated. Comparison with results at ultrasonic frequencies suggests existence a secondary relaxation. A change dependent viscosity from Vogel-Fulcher-Tammann behavior another regime low temperatures is also found. Compared most...

The mechanical response of ethylcyclohexane has been investigated at ultrasonic frequencies in a large temperature range from 300 K down to the glass transition region. results indicate existence secondary relaxation not yet reported for this system. comparison with literature data leads rather complex dynamic behavior. In fact, molecular liquid exhibits three different relaxations above temperature: main structural process and two additional processes, both having possible intramolecular origin.

To quantify the thermally activated relaxations of mobile silver ions in superionic phosphosulphate ${({\mathrm{Ag}}_{2}\mathrm{S}{\mathrm{O}}_{4})}_{x}{(\mathrm{AgP}{\mathrm{O}}_{3})}_{(1\ensuremath{-}x)}$ and phosphosulphide ${({\mathrm{Ag}}_{2}\mathrm{S})}_{x}{(\mathrm{AgP}{\mathrm{O}}_{3})}_{(1\ensuremath{-}x)}$ glasses, broad attenuation peaks reported previously have been analyzed terms a Gaussian-type energy distribution. The parameters obtained are used to determine influence...

Abstract The dielectric properties of (Ag2S) x ( AgPO3)1‐x and AgPO3 ionic glasses have been investigated at low frequencies (10 Hz‐10 MHz) by complex impedance measurements in the temperature range between 20 330 K microwave (8.2–18 GHz) using a waveguide transmission line also cavity resonator 9 GHz from 77 to 300 K. Analysis on basis jump relaxation model has shown that translational reorientational hopping motions mobile Ag+ ions are responsible for observed frequency‐dependent ac...

A low-temperature ultrasonic study of AgI-${\mathrm{Ag}}_{2}$O-${\mathrm{B}}_{2}$${\mathrm{O}}_{3}$ superionic glasses is presented. We show that for T<10 K the acoustic behavior governed by two-level-system (TLS) phonon-assisted relaxation. The analysis sound-velocity data seems to suggest TLS-phonon interactions are essentially a two-phonon or first-order Raman relaxation process T>3 K. TLS density states P\ifmmode\bar\else\textasciimacron\fi{} does not follow recently proposed...