SeqQuest: Thanks to…

SeqQuest is an electronic structure code developed at Sandia National Laboratory in an effort led by Peter A. Schultz. The success of any significant coding effort such as SeqQuest is not the work of a single individual, but is due to the contributions, both knowing and unknowing, of a large number of people. The method and code are descended from the work of Peter Feibelman. Collaboration with Bill Goddard’s group at Caltech has been critical to furthering Quest as a viable electronic structure method development effort. A variety of people made important contributions to SeqQuest, including:

Dr. Richard P. Muller (Sandia, formerly Caltech) Designed the development system (esp. test suites). Designed the cell optimization scheme implemented in SeqQuest. Wrote the molecular dynamics (MD) integrators in Quest.

Dr. Peter J. Feibelman (Sandia) Formulated the basic method used in implementing the Gaussian code, and the current SeqQuest code is descended from the original slab code he wrote.

Dr. Arthur H. Edwards (Air Force Research Laboratory) Wrote the post-processing code (DOS, pDOS, Mulliken analyses) for Quest, and developed the band structure code. Assisted Aidan in developing the NEB, and was particularly helpful in porting the code to MPI clusters.

Dr. Dwight R. Jennison (Sandia, retired) Dwight’s expansive research interests drove the development of the code toward a broad general purpose applicability. Good problems drive good methods development, and Dwight challenged Quest with a seemingly endless, and varied set of interesting, difficult physics modeling problems.

Prof. William A. Goddard III, and his group at Caltech Bill’s interest and commitment to the Quest effort, and the active collaboration of members of his group enabled Quest to grow beyond the lean development years and reach the level it has. His invitation to spend a year visiting the rich environment of his group at Caltech was both very enjoyable and very productive.

Ms. Carolina E. Mattsson (Sandia) Constructed the atom library on-line download web pages (not yet posted) Built the PP from the original generator files, performed the reference energy calculations, made the PP plots, and constructed web pages where all of these could be downloaded.

Dr. Aidan P. Thompson (Sandia) Designed SeqQuest’s transition state finder based on the nudged elastic band (NEB) method. Implemented the “parallel-parallel” NEB – parallel NEB, with task-parallel images.

Dr. Renee M. Van Ginhoven (PNNL, formerly Sandia) Added features and analysis tools to the NEB capability. Developing new geometry minimization coordinate scheme.

Dr. Ann E. Mattsson (Sandia) Implemented new DFT functionals (BLYP, AM05). Developed formalism and implemented stress for spin-polarized GGA.

Dr. Rudy J. Magyar (Sandia) Implemented spin version of AM05.

Dr. Andrew C. Pineda (UNM/AFRL) Helped install the upgrade from task-parallelism to distributed (esp. k-parallelism) parallelism in version 2.62.

Dr. David B. Raczkowski (formerly UCDavis, LBNL) Designed and wrote a linear solver for SeqQuest. Along the way, he identified the LAPACK expert eigensolvers that SeqQuest now uses for its highly efficient conventional solution of Schrodinger’s equation, pointed out how to integrate BLAS/3 routines for faster evaluation of compute-intensive grid integrals, and developed an eigenfunction-based scheme for computing the grid density that is faster than the default density-matrix scheme for modest-sized problems.

Dr. Jamil Tahir-Kheli (Caltech) Development of method for external applied electric field.

Dr. Dean McCoullough (HPTi) Initial development of the parallel algorithms for the cluster parallel” code, i.e., non-scalable, “task-distributed” parallelism.

Dr. Roland Stumpf (Sandia) The idea of using single precision arithmetic in the evaluation of integrals on the grid came from a conversation with Roland.