Gaussian Approximation Potential for Iron

The Gaussian Approximation Potential scheme is not limited to simple semiconductors. We demonstrate this by applying the scheme to a metallic system, namely the body-centred cubic (bcc) phase of iron. We included configurations in the training set where the lattice vectors of the one-atom primitive cell were randomised and where the positions of the atoms in 8 and 16-atom supercells were also 

GAP potential. The errors in the frequencies can be attributed to our Density Functional Theory calculations. 

The elastic moduli calculated with our model, the Finnis-Sinclair potential [14] and Density Functional Theory are given in Table 6.5. The elastic properties and the phonon dispersion relations described by the GAP model show excellent agreement with the values calculated by Density Functional Theory. 

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