In this manuscript, we extend on our prior work to show that under certain conditions cross-slip nucleation is athermal and spontaneous with zero activation energy in FCC elemental metals such as Ni and Cu, and L12 intermetallic compounds such as Ni3Al. Using atomistic simulations (molecular statics), we show that spontaneous cross-slip occurs at mildly repulsive intersections. Further, the loc...

We report the first atomistic calculation of the saddle-point configuration and activation energy for the nucleation of a 3D dislocation loop from a stressed crack tip in single crystal Cu. The transition state is found using reaction pathway sampling schemes, the nudged elastic band, and dimer methods. For the (111)[110] crack, loaded typically at 75% of the athermal critical strain energy rel...

We study the spontaneous nucleation and growth of sodium chloride crystals induced by controlled evaporation in confined geometries (microcapillaries) spanning several orders of magnitude in volume. In all experiments, the nucleation happens reproducibly at a very high supersaturation S ∼ 1.6 and is independent of the size, shape, and surface properties of the microcapillary. We show from class...

Direct atomistic simulations of dislocation multiplication in fcc aluminum reveal an unexpected mechanism, in which a Frank-Read source emits dislocations with Burgers vectors different from that of the source itself. The mechanism is traced to a spontaneous nucleation of partial dislocation loops within the stacking fault. Understanding and a quantitative description of this unusual process ar...

When the two eyes view incompatible images that subtend the entire visual field, perception alternates between the two images unpredictably: at seemingly random times and locations, observers experience sudden changes in the awareness of the unchanging visual stimulation. Here we focus on the very first spontaneous breakout from the very first suppression phase after onset of the two eyes' comp...

Research has been conducted to develop a new means of producing large grained polycrystlline thin films for photovoltaic applications. The process is one of growth of controlled crystalline nuclei in an a-Si film. For this process to be practicle, we must develop a-Si films with crystallization behavior such that the rate of spontaneous crystallization (nucleation rate) is essentially zero at t...

Free radicals in atmosphere have played an important role in the atmospheric chemistry. The chloro-Criegee free radicals are produced easily in the decomposition of primary ozonide (POZ) of the trichloroethylene, and can react with O2, NO, NO2, SO2 and H2O subsequently. Then the inorganic salts, polar organic nitrogen and organic sulfur compounds, oxygen-containing heterocyclic intermediates an...

Spontaneous asymmetric generation of supramolecular chiral fibers was observed in the folding induced self-assembly of a lock-washer shaped foldamer. A secondary nucleation growth mechanism is proposed to explain the observed chiral amplification or deracemization of these supramolecular fibers.

The crystallization behavior of (RS)-Diprophylline (DPL) in two different solvents is investigated in order to assess the incidence of solvated pre-associations on nucleation, crystal growth and chiral discrimination. In the solvated state, Raman spectroscopy shows that dimeric associations similar to those depicted in the crystalline solid solution (ssRII) predominate in isopropyl alcohol (IPA...

1. Whewellite (calcium oxalate monohydrate) crystals were found to induce epitaxially the heterogeneous nucleation of brushite (calcium monohydrogen phosphate dihydrate) from its metastable supersaturated solution in approximately one-quarter of the time required for spontaneous precipitation in the absence of added nucleating agents. Scanning electron-microscope observation of the crystalline ...