Computational studies of chemical systems
Our project ‘Computational studies of chemical systems’ has been allocated resources on the Swedish national supercomputer facilities since 2000. During 2016 we used 60% of the 200 000 CPU hours/month allocated on Abisko, 36% of the 150 000 CPU hours/month allocated on Tintin and 75% of the 150 000 CPU hours/month allocated on Triolith. This is a total usage of approximately 287 CPU hours/month and we therefore did not apply for a renewed large allocation. Instead we apply for a medium sized allocation for 12 months and as specified below. We are experienced users of SNIC resources and all of the programs that we will use run on these resources. This project combines the following three sub-projects: i) Polymer actuators for soft robotics.This subproject is being done in collaboration with experimental studies at the School of Textiles, University of Borås and macroscopic modelling at the University of Skövde. There have been several reports of the negative thermal expansion of polymer fibres. One polymer that shows negative thermal expansion is poly(vinylidene fluoride) (PVDF). We are performing molecular level simulations to reveal the molecular mechanism of this behaviour, with the aim of identifying materials that have better actuation properties. Post-doc Abas Mohsenzadeh and guest PhD student Mina Arja will work on this sub-project. One article, that ackowledges SNIC, was published in this sub-project during 2016. ii) Properties of polymer composites. This sub-project focuses on the mechanical properties of polymer composites as well as the permeation of oxygen or water through these composites. Since there is an increasing industrial interest in polymer nanocomposites, partly due to their good mechanical and barrier properties, we are studying how additives such as carbon black can be used to control their mechanical and barrier properties. It is expected that molecular-level understanding of the permeation mechanism, and the material properties that affect the permeation, will allow for the identification of nanocomposites with desired barrier properties. Gibbs Ensemble Monte Carlo (GEMC) is used to obtain the solubility coefficient (S) and molecular dynamics (MD) is used to obtain the diffusion coefficient (D). The permeation coefficient is the product of S and D (P=S*D). Dr Martin Bohlen will work in this sub-project during 2017. One article, that ackowledges SNIC, was published in this sub-project during 2016. iii) Reaction mechanisms and rates relevant for combustion reactions. The work is done in close collaboration with Prof. Tobias Richards, who leads the experimental research in thermal treatment of waste at the University of Borås. We are using density functional theory (DFT) to calculate adsorption, reaction and activation energies of the important elementary steps of relevance to combustion chemistry. These will then be used in kinetics modelling. Post-doc Abas Mohsenzadeh and guest PhD student Mina Arja will work on this sub-project. Three articles, that ackowledge SNIC, were published in this sub-project during 2015-2016.