Abstract: Towards Highly Accurate Large-Scale Ab Initio Calculations Using Fragment Molecular Orbital Method in GAMESS

Summary form only given. One of the major challenges of modern quantum chemistry (QC) is to apply it to large systems with thousands of correlated electrons and basis functions. The availability of supercomputers and development of novel methods are necessary to realize this challenge. In particular, we employ linear scaling Fragment Molecular Orbital (FMO) method which decompose the large system into smaller, localized fragments which can be treated with high-level QC method like MP2. FMO is inherently scalable since the individual fragment calculations can be carried out simultaneously on separate processor groups. It is implemented in GAMESS, a popular ab-initio QC program. We present the scalability and performance of FMO on Intrepid (Blue Gene/P) and Blue Gene/Q systems at ALCF.