Petascale resources and CP2K: enabling sampling, large scale models or correlation beyond DFT

Already with modest computer resources, GGA DFT simulations of models containing a few hundred atoms can contribute greatly to chemistry, physics and materials science. With the advent of petascale resources, new length, time and accuracy scales can be explored. Recently, we have made progress in all three directions: \begin{enumerate} \item A novel Tree Monte Carlo (TMC) algorithm introduces a further level of parallelism and allows for generating long Markov chains. Sampling 100'000s of configurations with DFT, the dielectric constant and order-disorder transition in water ice Ih/XI has been studied.[1] \item The removal of all non-linear scaling steps from GGA DFT calculations and the development of a massively parallel GPU-accelerated sparse matrix library make structural relaxation and MD possible for systems containing 10'000s of atoms.[2] \item A well parallelized implementation of a novel algorithm to compute four center intergrals over molecular states (RI-GPW), allows for many-body perturbation theory (MP2, RPA) calculations on a few hundred atoms. Sampling liquid water at the MP2 level yields a very satisfying model of liquid water, without empirical parameters.[3,4] \end{enumerate} References:\\[0pt] [1] Mandes Sch\"onherr, Ben Slater, J\"rg Hutter, and Joost VandeVondele, submitted. \newline [2] Joost VandeVondele, Urban Borstnik, J\"urg Hutter, JCTC 8, 3565 (2012) \newline [3] Mauro Del Ben, Mandes Sch\"onherr, J\"urg Hutter, and Joost VandeVondele JPCL 4, 3753 (2013) \newline [4] Mauro Del Ben, J\"urg Hutter, and Joost VandeVondele, JCTC 9, 2654 (2013) \newline