Articles

 

Bayesian Approach to Probabilistic Design Space Characterization: A Nested Sampling Strategy

Kennedy P. Kusumo, Lucian Gomoescu, Radoslav Paulen, Salvador García Muñoz, Constantinos C. Pantelides, Nilay Shah, and Benoît Chachuat

This paper investigates Bayesian approaches to design space characterization, which determine a feasibility probability that can be used as a measure of reliability and risk by the practitioner. An adaptation of nested sampling—a Monte Carlo technique introduced to compute Bayesian evidence—is presented. The nested sampling algorithm maintains a given set of live points through regions with increasing probability feasibility until reaching a desired reliability level.  It is shown that nested sampling can outperform conventional Monte Carlo sampling and be competitive with flexibility-based optimization techniques in low-dimensional design space problems. 

Industrial & Engineering Chemistry Research, 2020

https://doi.org/10.1021/acs.iecr.9b05006


Computationally efficient identification of probabilistic design spaces through application of metamodeling and adaptive sampling

Sergei Kucherenko, Dimitrios Giamalakis, Nilay Shah, Salvador García-Munoz

This article proposes a novel theoretical and numerical framework for determining probabilistic Design Space (DS) using metamodelling and adaptive sampling. The new multi-step adaptive technique uses a metamodel for a probability map as an acceptance-rejection criterion to optimize sampling to identify the DS. It is shown that application of metamodel-based filters can significantly reduce model complexity and computational costs with speed up of two orders of magnitude observed here.

Computers & Chemical Engineering, 132(4) 2020.

https://doi.org/10.1016/j.compchemeng.2019.106608


Accurate and efficient representation of intramolecular energy in ab initio generation of crystal structures. II. Smoothed intramolecular potentials

I.J.Sugden, C.S.Adjiman & C.C. Pantelides

This article describes a recent advance in the CrystalPredictor code for crystal structure prediction, namely a smoothed intramolecular potential, that improves the accuracy and efficiency of calculations, allowing for investigations into larger and more flexible molecules. It is illustrated with four case studies into large flexible molecules: ROY, glucose, molecule (XXVI) and flufenamic acid.

Acta Cryst. 2019,  B75, P423-433

https://doi.org/10.1107/S2052520619005778


Efficient screening for ternary molecular ionic cocrystals using a complementary mechanosynthesis and computational structure prediction approach

Shunnar AF, Dhokale B, Karothu DP, Bowskill DH, Sugden IJ, Hernandez HH, Naumov P, Mohamed S 

This article demonstrates that mechanochemical ball milling is a versatile technique for the reproducible synthesis of ternary molecular ICCs in less than 30 min of grinding with or without solvent. Computational crystal structure prediction (CSP) calculations have been performed on ternary molecular ICCs for the first time and the observed crystal structures of all the ICCs were correctly predicted. Periodic dispersion‐corrected DFT calculations revealed that all the ICCs are thermodynamically stable (mean stabilization energy=−2 kJ mol−1) relative to the crystallization of a physical mixture of the binary salt and acid. The results suggest that a combined mechanosynthesis and CSP approach could be used to target the synthesis of higher‐order molecular ICCs with functional properties.

Chemistry A European Journal (Chemistry Europe), 2019

https://doi.org/10.1002/chem.201904672


Polymorphism in p-aminobenzoic acid

Cruz-Cabeza AJ, Davey RJ, Oswald IDH, Ward MR, Sugden IJ

This article reviews the polymorphism of p-aminobenzoic acid (pABA), a model drug compound whose crystallisation and polymorphic behaviour has been extensively studied in recent years.  Crystal structure prediction calculations have been carried out in order to probe the solid form energy landscape of this compound. CrystEngComm, 2019, Advance Article, 10.1039/C8CE01890A

CrystEngComm, Royal Society of Chemistry, 2019

https://doi.org/10.1039/C8CE01890A


 

Conference papers and posters

Prediction of the solubility of active pharmaceutical ingredients under varying conditions of pH and temperature using the SAFT-γ Mie equation of state 

M Wehbe, CS Adjiman, G Jackson, A Galindo

2019 AIChE Annual Meeting, Orlando, FL - November 2019


A combined theoretical and experimental investigation into the  high-throughput  screening of cocrystal coformers

IJ Sugden, D Braun , CS Adjiman, CC Pantelides 

2019 AIChE Annual Meeting, Orlando, FL - November 2019

ECM 32 - 32nd European Crystallographic MeetingVienna, Austria -  18-23 August 2019

50th Meeting of British Association of Crystal Growth (BACG), London, UK - 9-10 July 2019


A flexible Lattice Dynamics approach for Free Energy calculations within Crystal Structure Prediction studies - Poster

SE Konstantinopoulos, IJ Sugden,  CS Adjiman & CC Pantelides

PhD Symposium of the Department of Chemical Engineering of Imperial College London, London, UK - 1 July 2019

50th Meeting of British Association of Crystal Growth (BACG), London, UK - 9-10 July 2019

Materials & Molecular Modelling Hub Conference and User Meeting 2019, London - 3-4 September 2019


Semi-empirical model of twin screw feeders for continuous pharmaceutical tablet manufacturing process 

D Bascone, F Galvanin, N Shah, S Garcia-Munoz

The Foundations of Computer-Aided Process Design (FOCAPD) Conference 2019, Colorado, USA - July 2019


An atomistic Lattice Dynamics approach for Free Energy calculations within Crystal Structure Prediction studies

SE Konstantinopoulos, IJ Sugden,  CS Adjiman & CC Pantelides

2019 Rational Solid Form Design Summit, Boston MA, USA - 21 -22 October 2019


Applicability of a Lattice Energy Model Used in Crystal Structure Prediction to Organic Hydrates

Y Zhang, IJ Sugden, CC Pantelides, CS Adjiman

2019 Rational Solid Form Design Summit, Boston MA, USA - 21 -22 October 2019


Application of global sensitivity analysis for constrained models and visualization

S. Kucherenko, O.V. Klymenko, N. Shah, S. García-Munoz

9th International Conference on Sensitivity Analysis of Model Output,  28 October 2019, Spain


Improved efficiency  in the ab initio generation of crystal structures

IJ Sugden, CS Adjiman, CC Pantelides

2018 AIChE Annual Meeting, Pittsburgh PA - 28 October - 2 November 2018


Accurate and efficient representation of intramolecular energy in ab initio generation of crystal structures. Part II: Smoothed Intramolecular potentials

IJ Sugden, CS Adjiman, CC Pantelides 

31st European Crystallographic Meeting, Oviedo, Spain - 22-27 August 2018


Free energy calculations for crystal structure prediction

SE Konstantinopoulos, IJ Sugden,  CS Adjiman & CC Pantelides

Methods and applications of crystal structure prediction Faraday Discussion, Cambridge, UK - 11-13 July 2018

Centre for Process Systems Engineering

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