Theoretical perspective on the glass transition and amorphous materials

Berthier, Ludovic; Biroli, Giulio

doi:10.1103/revmodphys.83.587

Cited by 1,945 publications

(2,433 citation statements)

References 499 publications

(524 reference statements)

Supporting

Mentioning

2,350

Contrasting

Unclassified

Order By: Relevance

“…This technique has the remarkable ability to treat simple and complex systems with equal ease, from monatomic to molecular liquids, molten salts, colloids, polymers, and large organic molecules in the liquid phase. Diverse and valuable reviews are available [20][21][22][23]. For normal and supercooled liquids, MD data for the MSD time evolution [24] has a well established interpretation in terms of the atomic motion [25].…”

Section: Comparison Of Theoriesmentioning

confidence: 99%

V-T theory for the self-intermediate scattering function in a monatomic liquid

Wallace

Chisolm

Lorenzi-Venneri

2016

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

In V-T theory the atomic motion is harmonic vibrations in a liquid-specific potential energy valley, plus transits, which move the system rapidly among the multitude of such valleys. In its first application to the self intermediate scattering function (SISF), V-T theory produced an accurate account of molecular dynamics (MD) data at all wave numbers q and time t. Recently, analysis of the mean square displacement (MSD) resolved a crossover behavior that was not observed in the SISF study. Our purpose here is to apply the more accurate MSD calibration to the SISF, and assess the results. We derive and discuss the theoretical equations for vibrational and transit contributions to the SISF. The time evolution is divided into three successive intervals: the vibrational interval when the vibrational contribution alone accurately accounts for the MD data; the crossover when the vibrational contribution saturates and the transit contribution becomes resolved; and the diffusive interval when the transit contribution alone accurately accounts for the MD data. The resulting theoretical error is extremely small at all q and t. Comparison of V-T and mode-coupling theories for the MSD and SISF reveals that, while their formulations differ substantially, their underlying atomic motions are in logical correspondence.

show abstract

Section: Comparison Of Theoriesmentioning

confidence: 99%

V-T theory for the self-intermediate scattering function in a monatomic liquid

Wallace

Chisolm

Lorenzi-Venneri

2016

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

show abstract

“…[22]. The time dependence of T f (L) is reminiscent of the conventional glass transition [38], that "is not a thermodynamic transition at all, since T g is only empirically defined as the temperature below which the material has become too viscous to flow on a 'reasonable' time scale...."…”

Section: Analysis and Comparison With Theoriesmentioning

confidence: 99%

Glassy dynamics in CuMn thin-film multilayers

et al. 2017

View full text Add to dashboard Cite

Thin film multilayered spin glass CuMn/Cu structures display glassy dynamics. The freezing temperature, T f , was measured for forty layers of CuMn films of thickness L = 4.5, 9.0, and 20.0 nm, sandwiched between non-magnetic Cu layers of thickness ≈ 60 nm. The Kenning effect, T f ∝ ℓn L, is shown to follow from power law dynamics where the correlation length grows from nucleation as ξ(t, T ) = c1a0(t/τ0) c 2 (T /Tg ) , leading to [(T f /Tg)c2ℓn(tco/τ0)] + ℓnc1 = ℓn(L/a0). Here, Tg is the bulk spin glass temperature, c1 and c2 are constants determined from the spin glass dynamics, tco is the time for the correlation length to grow to the film thickness, τ0 is a characteristic exchange time ≈ /kBTg, and a0 is the average M n − M n separation. For t ≥ tco, the magnetization dynamics are simple activated, with a single activation energy ∆max(L)/kBTg = (1/c2)[ℓn(L/a0) − ℓnc1] that does not change with time. Values for all these parameters are found for the three values of L explored in these measurements. We find experimentally ∆max(L)/kB = 907 K, 1,246 K, and 1,650 K, respectively, for the three CuMn thin film multilayer thicknesses, to be consistent with power law dynamics. We perform a similar analysis based on the activated dynamics of the droplet model, and find a much larger spread for ∆max(L) than found experimentally.

show abstract

“…The glass state is obtained when, upon cooling or pressurizing fast enough to avoid the transition to the crystalline state, a liquid gradually freezes, into an amorphous phase in which the molecular motions are quenched while the structural disorder of the liquid is retained. [1][2][3][4] A glass-like dynamics may appear also when a translational long-range order exists. In fact, many molecular systems form phases which are characterized by translational order and at the same time by orientational disorder.…”

Section: Introductionmentioning

confidence: 99%

Double Primary Relaxation in a Highly Anisotropic Orientational Glass-Former with Low-Dimensional Disorder

et al. 2016

View full text Add to dashboard Cite

The freezing of the cooperative reorientational motions in orientationally disordered (OD) molecular crystals marks the so-called "glassy" transition, which may be considered a lower-dimensional version of the structural glass transition. While structural glasses display both positional and orientational disorder, in fact, in orientational glasses the disorder involves exclusively the orientational degrees of freedom of the constituent molecules, while the molecular centres of mass form an ordered lattice. We report here on a glass-forming system with even less degrees of freedom, namely the OD phase of a dipolar benzene derivative, pentachloronitrobenzene (C 6 Cl 5 N O 2 ). We probe the orientational dynamics of PCNB as a function of temperature and pressure * To whom correspondence should be addressed † Universitat Politècnica de Catalunya ‡ Università di Pisa 1 by means of dielectric spectroscopy at normal and high pressure and high-pressure density measurements, and show that the system exhibits a double primary relaxation feature associated with two distinct motions of the molecular dipole moment. After ruling out an interpretation in terms of primitive or intramolecular relaxations, we discuss an assignment of the double relaxation feature based on the material's anisotropy and on the comparison with discotic liquid crystals.

show abstract

Theoretical perspective on the glass transition and amorphous materials

Cited by 1,945 publications

References 499 publications

V-T theory for the self-intermediate scattering function in a monatomic liquid

V-T theory for the self-intermediate scattering function in a monatomic liquid

Glassy dynamics in CuMn thin-film multilayers

Double Primary Relaxation in a Highly Anisotropic Orientational Glass-Former with Low-Dimensional Disorder

Contact Info

Product

Resources

About