Parallelization of the polarizable embedding scheme for higher-order response functions

Abstract

We present a parallel implementation of the Polarizable Embedding (PE) method, an advanced quantum mechanics/molecular mechanics (QM/MM) approach, for Hartree–Fock (PE-HF) and density functional theory (PE-DFT). The parallelization includes calculations of energies and linear, quadratic, and cubic response functions. The couplings to the QM system due to the polarizable embedding potential have been implemented using a master/slave approach. The implementation shows good scaling behaviour, demonstrated through calculations on a small (a water molecule in a bulk of water molecules) and a larger system (Green Fluorescent Protein (GFP)).

Keywords:

• polarizable embedding
• parallel calculations
• excitation energies
• response theory

Acknowledgements

This work has received support from the Research Council of Norway through a Center of Excellence grant (Grant No. 179568/V30) and from the European Research Council through a Starting Grant (Grant No. 279619). Support from the Norwegian Supercomputing Program through a grant of computer time is also gratefully acknowledged. J.K. thanks The Danish Councils for Independent Research (STENO and Sapere Aude programmes), the Lundbeck Foundation and the Villum Kann Rasmussen Foundation for financial support.