Ewald summation based on
non-uniform fast Fourier transform
ENUF is good enuf |
To calculate the electrostatic (Coulombic) energies and forces in molecular computer simulations is the by far most time-consuming part due to their longranged interactions. We have recently presented a novel approach by combining the traditional Ewald summation technique with the nonuniform Fast Fourier transform. This method is both highly efficient, scaling as O(NlogN), and straight forward to implement in existing simulation programs by utilizing widely available libraries. It should be mentioned that the so called particle mesh Ewald (PME) method (also scaling as NlogN) has been the state of the art for one decade and made it possible to perform largescale simulations (like proteins in physiologically relevant environments). It could be worth of mentioning that the PME method was elected as the ”method of the century” on a large simulation algorithm conference for three years ago. However, the PME method is clearly less accurate and less stable that our Ewald with Non-Uniform Fourier transform (ENUF) method. Our ENUF conserves BOTH energy AND momentum. PME does not do it currently. In this project we will improve the parallel scaling properties of ENUF and implement a version using nonperiodic boundary conditions. The ENUF method will certainly become a very significant contribution to the field. We there wish to develop it further by ourselves rather than just give it away as a concept.
Fredrik Hedman and Aatto Laaksonen, Ewald summation based on non-uniform fast Fourier transform Fredrik Hedman, Algorithms for Molecular Dynamics Simulations, Doctoral Thesis, Stockholm University (2006).
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