We perform molecular dynamics simulations to study the structural relaxation dynamics of a model of viscous silica, the prototype of a strong glass former. We find that the melt dynamics are spatially heterogeneous regardless of whether the bulk relaxation is non-Arrhenius or Arrhenius, and cannot be understood as a statistical bondbreaking process. Further, we show that stringlike motion is su...

Many 4øAr/39Ar age spectra for alkali feldspars are significantly different from the model age spectra calculated for slowly cooled samples composed of diffusion domains of a single size, and the Arrhenius plots for these samples show departures from linearity that are inconsistent with diffusion from domains of equal size. The most plausible explanation for these discrepancies is the existence...

Arrhenius-type plots for multifragmentation process, defined as the transverse energy dependence of the single-fragment emission-probability, (ln(1/pb) vs 1/ √ Et), have been studied by examining the relationship of the parameters pb and Et to the intermediate-mass fragment multiplicity 〈n〉. The linearity of these plots reflects the correlation of the fragment multiplicity with the transverse e...

Arrhenius plots of fluoride- and guanine-nucleotide-stimulated adenylate cyclase activity were linear in adipocyte plasma membranes from lean and obese (ob/ob) mice. Arrhenius plots of isoprenaline-stimulated adenylate cyclase activity in hepatic plasma membranes biphasic in both groups. The results were biphasic in membranes from lean mice but linear in membranes from obese mice. In contrast, ...

The validity of the Arrhenius equation for dissociative electron attachment rate coefficients is investigated. A general analysis allows us to obtain estimates of the upper temperature bound for the range of validity of the Arrhenius equation in the endothermic case and both lower and upper bounds in the exothermic case with a reaction barrier. The results of the general discussion are illustra...

Ionic transport in conventional ionic solids is generally considered to proceed via independent diffusion events or "hops." This assumption leads to well-known Arrhenius expressions for transport coefficients, and is equivalent to assuming diffusion is a Poisson process. Using molecular dynamics simulations of the low-temperature B1, B3, and B4 AgI polymorphs, we have compared rates of ion hopp...

A major mystery of glass-forming liquids is the non-Arrhenius temperature-dependence of the average relaxation time. This paper brie ̄y reviews the classical phenomenological models for non-Arrhenius behavior ± the free volume model and the entropy model ± and critiques against these models. We then discuss a recently proposed model according to which the activation energy of the average relaxat...

Molecular dynamics simulations have been used extensively to model the folding and unfolding of proteins. The rates of folding and unfolding should follow the Arrhenius equation over a limited range of temperatures. This study shows that molecular dynamic simulations of the unfolding of crambin between 500K and 560K do follow the Arrhenius equation. They also show that while there is a large am...