Atomic insight into iron corrosion exposed to supercritical water environment with an improved Fe-H2O reactive force field

Effect of Fe–O ReaxFF on Liquid Iron Oxide Properties Derived from Reactive Molecular Dynamics

“…Figure b shows the relative energy during the diffusion of an oxygen atom from one octahedral interstitial site to a neighboring site via a tetrahedral site. Based on DFT calculations, the energy barrier associated to diffusion are in the range of 11.07 and 13.84 kcal/mol, − with the maximum value located at the tetrahedral site . ReaxFF2010-full, ReaxFF2012, and ReaxFF2015 predict a minimum energy path (MEP) with negative values, where the latter two significantly deviate from zero.…”

“…Over the past few years, several improved force fields for iron have been reported. − Here, the impact of six different reactive force fields on the prediction of liquid iron oxide properties will be investigated, including those of Aryanpour et al (ReaxFF2010-ox and ReaxFF2010-full), Zou and van Duin (ReaxFF2012), Shin et al (ReaxFF2015), Islam et al (ReaxFF2016), and Huang et al (ReaxFF2022). Each ReaxFF parameter set was trained and used for a specific application: The ReaxFF reactive force field, developed by Aryanpour et al, is widely used to simulate the oxidation of Fe with either water or oxygen.…”

“…Zou and van Duin , used the O/H/Fe interactions proposed by Aryanpour et al to optimize their ReaxFF parameter set. Shin et al (ReaxFF2015) developed a ReaxFF force field to investigate the Cr oxide-catalyzed oxidation reaction of butane at a high temperature of 1600 K. This study considered the presence of iron pyrite (FeS 2 ), which can accelerate the complete oxidation of butane. Islam et al (ReaxFF2016) developed their ReaxFF parameter sets to study the interaction of hydrogen with pure and defective ferrite–cementite interfaces. They merged the ReaxFF force field that was developed for the FT synthesis (Fe–C–H system) , with a ReaxFF carbon parameter set and subsequently optimized the parameters. More recently, Huang et al (ReaxFF2022) investigated the corrosion mechanism of solid iron surfaces at 973, 1173, and 1373 K with water. Their research identified limitations in the ReaxFF parameter set proposed by Aryanpour et al, particularly in accurately describing the diffusion behaviors of hydrogen and oxygen within iron.…”

“…They merged the ReaxFF force field that was developed for the FT synthesis (Fe−C−H system) 55,62 with a ReaxFF carbon parameter set 63 and subsequently optimized the parameters. • More recently, Huang et al 58 54 particularly in accurately describing the diffusion behaviors of hydrogen and oxygen within iron. Therefore, they improved the initial parameters of Aryanpour et al 54 to optimize the Fe−Fe, Fe−O, and Fe− H parameter sets.…”

Atomistic insights into early stage corrosion of bcc Fe surfaces in oxygen dissolved liquid lead-bismuth eutectic (LBE-O)

“…Surface energies (J/m 2 ) of bcc Fe(100), Fe(110), and Fe(111). G-NN potential DFT(present) ReaxFF [32] Experiment [33] Fe( 100 It is well known that corrosion is also closely related to surface adsorption and other chemical reactions that may happen in certain corrosive environment. The adsorption energies of an adatom on different Fe surfaces at different sites have been calculated according to the following formula: [22]…”