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Enhancing structure relaxations for first-principles codes: an approximate Hessian approach

J. M. Rondinelli·B. Deng·L. D. Marks
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Abstract

We present a method for improving the speed of geometry relaxation by using a harmonic approximation for the interaction potential between nearest neighbor atoms to construct an initial Hessian estimate. The model is quite robust, and yields approximately a 30% or better reduction in the number of calculations compared to an optimized diagonal initialization. Convergence with this initializer approaches the speed of a converged BFGS Hessian, therefore it is close to the best that can be achieved. Hessian preconditioning is discussed, and it is found that a compromise between an average condition number and a narrow distribution in eigenvalues produces the best optimization.

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J. M. Rondinelli, B. Deng, L. D. Marks. 2006-11-13. Enhancing structure relaxations for first-principles codes: an approximate Hessian approach. https://doi.org/10.1016/j.commatsci.2007.01.004

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