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PyCAC features and non-features

Features

The PyCAC code can simulate monatomic pure face-centered cubic (FCC) or pure body-centered cubic (BCC) metals using the Lennard-Jones (LJ) or the embedded-atom method (EAM) potentials in a constant temperature field. In the coarse-grained domain, 3D trilinear rhombohedral elements are employed to accommodate dislocations in 9 out of 12 sets of $\{111\}\left<110\right>$ slip systems in an FCC lattice, as well as 6 out of 12 sets of $\{110\}\left<111\right>$ slip systems in a BCC lattice.

Non-features

While the CAC method is applicable to thermo/mechanical problems in almost all crystalline materials, current version of the PyCAC code has not yet been extended to simulate:

• dislocations in 12 sets of $\{112\}\left<111\right>$-type and 24 sets of $\{123\}\left<111\right>$-type slip systems in a BCC lattice;
• crystal structures other than FCC and BCC, e.g., simple cubic, diamond cubic, hexagonal close-packed;
• interatomic potentials other than LJ and EAM, e.g., Stillinger-Weber potential, Tersoff potential, or modified EAM (MEAM) potential;
• 1D or 2D materials that require 1D or 2D elements, respectively, as well as materials requiring 3D elements different from the rhombohedral ones;
• multicomponent, multi-constituent, multiphase, or polyatomic crystalline materials, e.g., alloys, intermetallics, composite materials, ceramic, mineral;
• materials in a non-constant temperature field.

Moreover, the adaptive mesh refinement scheme is not implemented in the current PyCAC code.