Two-dimensional FeC compound with square and triangle lattice structure – Molecular dynamics and DFT study

Formation of two-dimensional (2D) Fe-C alloy with square lattice structure from the liquid state is studied via molecular dynamics (MD) simulation. The researchers find that the crystallization of 2D Fe-C alloy exhibits a ﬁrst-order-like phase transition. Evolution of structural and thermodynamic properties upon cooling from the melt of the model is investigated in details. Structural properties of the Fe50C50 model are investigated via the radial distribution function (RDF), coordination number, interatomic distance, and bond-angle distributions. The researchers find that Fe-Fe distance is 2.62Å, which is close to the value of DFT calculations and experiments. In addition, various types of structural defects are studied such as vacancies of different shapes and rings of several sizes clearly using the visualization’s software Visual Molecular Dynamics (VMD). Moreover, it can be proposed that the 2D Fe-C material would have many important applications in electronics and mechanic devices.

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Molecular dynamics study of two dimensional and adsorbed microclusters

The Journal of Chemical Physics ◽

10.1063/1.439697 ◽

1980 ◽

Vol 72 (8) ◽

pp. 4562-4568 ◽

Cited By ~ 16

Author(s):

Mariana Weissmann ◽

Norah V. Cohan

Keyword(s):

Molecular Dynamics ◽

Two Dimensional

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Molecular Dynamics Simulations of Shock-Defect Interactions in Two-Dimensional Nonreactive Crystals

MRS Proceedings ◽

10.1557/proc-296-161 ◽

1992 ◽

Vol 296 ◽

Cited By ~ 2

Author(s):

Robert S. Sinkovits ◽

Lee Phillips ◽

Elaine S. Oran ◽

Jay P. Boris

Keyword(s):

Molecular Dynamics ◽

Hexagonal Lattice ◽

Square Lattice ◽

Two Dimensional ◽

Connection Machine ◽

Defect Sites ◽

Principal Axes ◽

Shock Motion ◽

Defect Interactions ◽

Dynamics Simulations

AbstractThe interactions of shocks with defects in two-dimensional square and hexagonal lattices of particles interacting through Lennard-Jones potentials are studied using molecular dynamics. In perfect lattices at zero temperature, shocks directed along one of the principal axes propagate through the crystal causing no permanent disruption. Vacancies, interstitials, and to a lesser degree, massive defects are all effective at converting directed shock motion into thermalized two-dimensional motion. Measures of lattice disruption quantitatively describe the effects of the different defects. The square lattice is unstable at nonzero temperatures, as shown by its tendency upon impact to reorganize into the lower-energy hexagonal state. This transition also occurs in the disordered region associated with the shock-defect interaction. The hexagonal lattice can be made arbitrarily stable even for shock-vacancy interactions through appropriate choice of potential parameters. In reactive crystals, these defect sites may be responsible for the onset of detonation. All calculations are performed using a program optimized for the massively parallel Connection Machine.

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