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Simulations machinery broadly available today allows direct-space solutions of crystal structures based on high quality powder diffraction data for systems with up to some 15–20 degrees of freedom. Analogous machinery for predicting new structures is rarely unsuccessful, but has had limited systematic application. The prime challenges for structure solution are for degrees of freedom beyond some 15–20, and for powder diffraction data which is of insufficient quality to allow an unambiguous indexing. In structure prediction, the corresponding issues are (i) enumeration strategies, (ii) collated access to the results of prior predictions, (iii) relating results in some fashion to likelihood of occurrence, encompassing finite temperature issues, and (iv) rational approaches to the synthesis of designed structures. Recent progress in the field has been steady and, while solutions to these key problems are not immediately obvious, the pace of progress over the past 5 years suggests major headway is imminent in a number of these areas.

Tight gas and shale gas represent a significant energy resource. These types of reservoirs are geologically complex and the reservoir flow processes involved are unusual. While some investigators have modeled various aspects of these systems, there is currently no consensus on the significance of microscale diffusion on flow behavior over time. Pore throat diameters on the order of nanometers are known to result in non-Darcy flow conditions, which can be accounted for using the dusty-gas model coupled with various models for diffusivity estimation. This phenomenon is related to the Klinkenberg effect. In this work we implement the dusty-gas model into a reservoir modeling tool based on the TOUGH+ code. We examine the effects of Knudsen diffusion on flowing gas composition at low permeability. We show that for rock with small pore throat diameters, the composition of flowing gas is significantly different than the in situ stagnant conditions. We describe how gas composition measurement could be used to identify flow boundaries in these reservoir systems. We present a fit-for-purpose numerical model based on the TOUGH+ code for modeling microscale transport effects. This work contributes: A new multicomponent microscale transport model A new, fit-for-purpose numerical model based on the TOUGH+ code capable of characterizing reservoir flow effects including permeability adjustment and diffusion in micro- and nano-scale porous media.

Simulation in catalyst and sorbent research spans a wide range of techniques and applications complementing and enhancing experimental approaches. This includes (i) model construction and visualization, (ii) materials characterization through simulation of experiments such as x-ray diffraction, (iii) atomistic simulations of dynamic processes such as docking and diffusion using empirical potentials, and (iv) quantum mechanical methods predicting chemical bonding and reactivity. Thorough technical validation, algorithmic and accessibility enhancements, and a strong industrial focus continue to drive key developments. The focus on practical catalyst and sorbent problems is illustrated here by (i) a simulation of the energetic diffusion barrier experienced by a toluene molecule in the microporous material boggsite and (ii) the structure, energetics and bond strengths of acidic protons in faujasite using a localized-orbital density functional approach.

A combination of computer modelling techniques has been applied in two areas: (1) A survey of the ability of organic molecules to template microporous materials. (2) A study of the behaviour of the sorption and diffusion of the various isomers of butene in the catalyst DAF-1.

Simulation studies employing energy minimisation, Monte Carlo (MC) and molecular dynamics (MD) techniques are now powerful techniques for the study of the docking and migration of sorbed molecules in zeolites. In this paper we present two recent and related applications of the techniques to contemporary problems in zeolite science.