ORDER-N TIGHT-BINDING MOLECULAR-DYNAMICS ON PARALLEL COMPUTERS

A recently proposed order-hr method for tight-binding molecular dynami cs is implemented on parallel machines. The Fortran code, written for the parallel computer CM-5, uses a general message passing library, be ing therefore highly portable. The main subjects of this implementatio n, which are matrix partition and sparse matrix multiplication, are di scussed in detail. We describe the assignment of work to each processo r and the parallelization of sparse matrix multiplications. The perfor mance of our parallel programs is analyzed by timing tests on a CM-5. Tt is shown that the program is both weakly and strongly scalable. Wit h the present code, tight-binding molecular dynamics simulations in sy stems with up to 85184 carbon atoms are possible on a CM-5 with 512 pr ocessors.