Enabling next generation quantum chemistry

This proposal addresses the need for advances to be made in the first-principles computation of electronic structure in order for progress to be possible on several of the chemical grand challenges. At present, some problems are completely inaccessible; these include:
. First-principles force field generation for biomolecules using the best electronic wavefunction methodology.
. Catalysis on the surface of entire 1000-atom metallic nanoparticles photoactive biology beyond time-dependent density functional theory.
. Predictive spectroscopy of solvated systems and chemical reactions in solution.

Traditionally, quantum chemistry codes are extremely complex, and require many man-years for development and subsequent maintenance. Over the years, these software systems have been developed in an ad-hoc way, driven by the need to express new science quickly, and often without abstraction of key generic components for single optimal implementation. Unfortunately, this presents barriers for progress. New HPC systems are difficult to exploit when data and task management are not abstracted. Implementation of new theories and new algorithms is held back by present code complexity. Furthermore, the multiple output models of different codes hinder post- and pre-processing; a single agreed extensible model would be better.

This proposal is an application for preliminary travel funding in order to maintain and strengthen the links between the UK and US researchers for this project that were established in the joint EPSRC-NSF workshop that was held in June 13-15 in Oxford.

We expect that the meetings we propose will lead to joint UK-US projects that will have a wide impact: to researchers in academia and in industry, as well as eventually to society in general. The quantum chemistry methods that we describe in this project are the tools that underpin the solution of many chemical grand challenge problems. For example, the quality of force fields, which are used for simulations of biomolecular and materials properties depends crucially on the availability of high quality ab initio calculations to parameterise them. There are also a multitude of chemical challenges that cannot be tackled with force fields, such as applications that require description of charge transfer and polarisation and/or involve chemical reactions. For these, the inclusion of electrons by ab initio calculations is essential. The ab initio simulation codes that we describe in this proposal and the developments envisaged have particular application in areas such as drug development, chemical reactions in solution, simulation of spectra (which are the probes with which we can characterise matter in the laboratory) and also catalysis on the surface of metallic nanoparticles. The industrial and societal relevance of these developments is high: for example Dr Skylaris has collaborations with Boehringer Ingelheim (drug design and manufacturing ) and Johnson Matthey (development of metal nanoparticle catalysts for automotive and fuel cell applications) who would directly benefit from these developments. As the codes mentioned in this proposal are commercially available to industry, the capabilities for simulation that would be developed will contribute towards better and more effective drugs and energy applications, via creation of new products, and eventually to improvements in quality of life.