I'm stuck with a problem of finding the minimum energy of an inorganic crystal. Crystal is of monoclinic structure with 18 parameters to specify its internal coordinates and 2 atomic species. Am using a classical interatomic potential found in literature.(adsbygoogle = window.adsbygoogle || []).push({});

The minimization involves both the 18 parameters and the cell vectors.

Have tried conjugate gradient method but algorithm never gives me a satisfactory minimum - the L2-norm of the forces is far from zero.

The best results I got was with the Nelder-Mead simplex method. Even then, the L2-norm of the forces at the termination of the algorithm was not close to zero.

Any pointers? I was thinking of trying Damped MD next ...

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# Geometry Optimization of Crystals

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