Hydrogen embrittlement substantially decreases the mechanical strength of metallic systems, such as carbon steels, often leading to catastrophic failures in these materials. This is a particular problem for materials exposed to hydrogen, in particular the...
Highlights with ‘ReaxFF’
Dyes on TiO2: ReaxFF + TDDFT study
Reactive Molecular Dynamics simulations with ReaxFF have been used successfully in combination with Time-Dependent Density Functional Theory (TDDFT) calculations to disclose structural features, aggregation characteristics, dynamics and spectroscopic properties of an organic dye adsorbed on a...
H2 production by PAH gasification
The gasification of polycyclic aromatic hydrocarbons (PAHs) in supercritical water has been studied with a DFT and ReaxFF. Supercritical water decreases the barrier for the rate-determining ring opening of PAHs by over 550 kJ/mol, thereby accelerating...
Characterizing aqueous cysteine in bulk and at the surface
Reactive molecular dynamics simulations (ReaxFF) and X-ray photoelectron spectroscopy were used to investigate both the bulk and the surface distribution of cysteine species in aqueous solution. Experimentally, the protonation state of cysteine, which in water...
Cysteine nanodroplet on a titania surface
Molecular Dynamic simulations based on a reactive force field (ReaxFF) have been shown to be the most appropriate method to characterize the adsorption of droplets of cysteine molecules on TiO2 rutile (110) slabs producing results...
ReaxFF molecular dynamics simulations on lithium sulfur batteries
Understanding of the structural, and kinetic behavior of the sulfur cathode materials are crucial for designing high performance Li-S batteries. In a recent study, ReaxFF molecular dynamics simulations has been utilized to study sulfur cathode...
ReaxFF: Teflon coating reduces Li-S battery electrolyte decomposition
Lithium released from the anode is a highly exothermic process in lithium-sulfur batteries, and as such can lead to reactions with the electrolyte. In a recent ReaxFF study, the lithium discharge from a single-walled carbon...
Oriented Attachment of TiO2 Nanocrystals
The growth of TiO2 nano-particles has been studied with reactive molecular dynamics (ReaxFF) by researchers from Penn State. While in vacuum the particles aggregate in the orientation of approach, in aqueous phase the nanocrystals have...
Multi-scale Modeling of Chemistry in Water
Accurate modeling of chemical reactions in realistic aqueous environments calls for an efficient multi-scale quantum mechanical/molecular mechanical (QM/MM) approach. However, since solvent molecules diffuse in and out of the region of interest, new adaptive approaches...
Water adsorption and dissociation on titania surfaces with ReaxFF
Researchers from Penn State studied the adsorption and dissociation of water on various anatase surfaces and rutile (110) at various coverages with a newly developed reactive force field. The reactive MD calculations agree with previous...