Daubechies小波作为密度泛函赝势计算的基组

Daubechies Wavelets for Linear Scaling Density Functional Theory

We demonstrate that Daubechies wavelets can be used to construct a minimal set of optimized localized contracted basis functions in which the Kohn-Sham orbitals can be represented with an arbitrarily high, controllable precision. Ground state energies and the forces acting on the ions can be calculated in this basis with the same accuracy as if they were calculated directly in a Daubechies wavelets basis, provided that the amplitude of these contracted basis functions is sufficiently small on the surface of the localization region, which is guaranteed by the optimization procedure described in…

Fragment Approach to Constrained Density Functional Theory Calculations using Daubechies Wavelets

In a recent paper we presented a linear scaling Kohn-Sham density functional theory (DFT) code based on Daubechies wavelets, where a minimal set of localized support functions is optimized in situ and therefore adapted to the chemical properties of the molecular system. Thanks to the systematically controllable accuracy of the underlying basis set, this approach is able to provide an optimal contracted basis for a given system: accuracies for ground state energies and atomic forces are of the same quality as an uncontracted, cubic scaling approach. This basis set offers, by construction, a nat…

多核混合CPU-GPU结构的密度泛函理论计算

Density Functional Theory calculation on many-cores hybrid CPU-GPU architectures

提出了一种基于图形处理器（GPU）的混合并行结构的完整电子结构计算程序的实现方法。基于我们实现的代码是基于Daubechies小波的GNU-GPL代码。它表现出非常好的性能，系统的收敛性和并行计算机上的一个优秀的效率。我们基于GPU的加速完全保留了所有这些属性。特别地，代码能够在许多核上运行，这些核可能具有或可能不具有相关联的GPU。因此，它能够在并行和大规模并行混合环境中运行，也具有非均匀的CPU/GPU比率。利用双精度计算，我们可以实现相当大的加速，对于某些操作是20倍，对于整个DFT代码是6倍。