“BigData”inmaterials
modelling
AngelosMichaelides
ThomasYoungCentre,
LondonCentreforNanotechnology&DepartmentofPhysics&
Astronomy,
UniversityCollegeLondon(UCL),UK
www.chem.ucl.ac.uk/ice
www.thomasyoungcentre.org
Whatismaterials
modelling?
- Alsoknownasthetheory
andsimulationof
materials
- Increasinglyinvolvesthe
applicationofcomputers
tounderstandthe
propertiesofexistingand
newmaterials.
Themolecularmodelingrevolutionin
chemistry,physicsandbiology
Kilopapers
20
15
TOTAL
Force field
Density functional theory
Wave function theory
10
5
1991
1996
2001
Year
2006
2011
• Molecularlevelinsighttoexistingmaterials
• Examplesofmaterialsdiscoveryto:Catalysts,Batteries,
Highstrengthalloys,Hydrogenstorage,Thermoelectrics,…
Keywords used:
Topic=("HF" or "WFT" or "MP2" or "MCSCF" or "Hartree-Fock" or "post Hartree-Fock" or
Water: Themostanomalousliquid
…themostubiquitous,essentialforlife
Contemporaryconcernsforsociety:
(thatsciencecanhelpdirectlywith)
ClimateHealthEnergy
Directlyorindirectlyrelatedto
water;generallyatinterfaces
Materials modelling is now “data rich”
- Increasedcomputationalcapacity,improvedalgorithms
andcodesmeansmuchshortertimetosolution
- Bigdataissues,e.g.:
Identificationofnew
structures,polymorphs
ii) Exploration of processes
previously beyond reach
iii) More accurate evaluations
of e.g. E (energy)
HΨ = EΨ
i)
Nature Materials 15, 66 (2016)
1. New structures, polymorphs, materials
- Variousinternationaldatabasesemerging,e.g.MaterialsProject
(Berkeley/MIT), NoMaD (Berlin),CPOSS(UCL)
- Confinedwater:Crystalstructurepredictions:10,000+trial
structures,mining toidentifyinterestingones,descriptors to
explainproperties…
Phys.Rev.Lett116,025501(2016)
2.Newprocesses,e.g.iceformation
- Freezingofwater:notunderstoodatthemolecularlevel
- Mechanismdeterminedusingforwardfluxsampling– involving
~100,000trajectories(eachcontaining30,000atoms)
Patternrecognition:
• 5 million CPU hours
• 50,000 configurations
involved in the I/O
• 5 Terabytes of data
3. More accurate energies, e.g. water
Mostwidelyusedquantumapproach(DFT)forsimulations
ofliquidwaternotuptothejob…
Reference
StandardDFT
Prism
0.00
0.00
Cage
0.24
-0.59
Book
0.70
-2.18
Cyclic
1.69
-2.44
J.Chem.Phys.144,130901(2016)
Gaussianapproximationpotential
- Databaseofaccurate(~exact)energiesfor
watermonomers,dimers,trimers
- FitgeneralinteractionwithGaussianregression
Reference
StandardDFT
Machine
Learning
Prism
0.00
0.00
0.00
Cage
0.24
-0.59
0.15
Book
0.70
-2.18
0.52
Cyclic
1.69
-2.44
1.77
- Verygoodperformanceforiceandliquidwater…
TheThomasYoungCentre
• Interdisciplinaryallianceofabout80groupsworking
toaddresschallengesofsocietyandindustrythrough
theory&simulationofmaterials
• Imperial,King’s,QMUL,UCL;Chemistry,Physics,
EarthSciences,Materials,Engineering,Nanotech.
• Ahubforcollaborations&aportaltoastrong
interdisciplinaryresearchcommunityoperatingatthe
forefrontofscience;placing Londonatcentre
ofinternational materialsmodelling
• Formoreinformationsee:
www.thomasyoungcentre.org orthismonth’sedition
ofNatureMaterials(Volume15,page371(2016))
Conclusions
• Bigdataisabigissueinmaterials
modelling
• Bigdatarelevanttounderstanding
importantphysiochemicalproblems
www.chem.ucl.ac.uk/ice
• UCLmodellingandTYCarestrong
inthisfield
• Successreliesonextracting
physicalinsightfromdataand
accesstoworldclasscomputing
facilitiestogenerateit…
www.chem.ucl.ac.uk/ice
www.thomasyoungcentre.org
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