  The plane wave method is most widely used for solving the Kohn-Sham equations
in first-principles materials science computations. In this procedure, the
three-dimensional (3-dim) trial wave functions' fast Fourier transform (FFT) is
a regular operation and one of the most demanding algorithms in terms of the
scalability on a parallel machine. We propose a new partitioning algorithm for
the 3-dim FFT grid to accomplish the trade-off between the communication
overhead and load balancing of the plane waves. It is shown by qualitative
analysis and numerical results that our approach could scale the plane wave
first-principles calculations up to more nodes.
