Vector-parallel processing of Car-Parrinello method

First principles molecular dynamics program 'Camp Atami' is parallelized for VPP500, which is a vector parallel type supercomputer. The program is based on Car-Parrinello method, and includes common techniques frequently used in calculations of electronic structures. In order to get large granularity, the parallelization is conducted for each reciprocal lattice point and for each band index, and reached up to about 90% of the total code. Speedup ratio increases almost proportionally up to 4.4 times with the increase of processor number up to 8. A new 3 dimensional fast Fourier transform (FFT) program is made and parallelized. The result is found to be much faster than that provided as a subroutine library by restricting the number of data elements to the power series of 2. (author)