lammps和ovito简介PPT课件

.,1,AbriefintroductiontosimulationandvisualizationsoftwareLAMMPS、OVITO2017.10.20,.,2,1、Introductiontomoleculardynamics.2、WhatisLammps?3、CommandsofLammps.4、HowtousevisualizationsoftwareOVITO?,Reportcontent,.,3,AtomicdiffusionSurface,interface,defectCrystalgrowth,SolidphasetransitionMelting,solidification,amorphousformationMechanicalpropertiesPhonon,thermodynamicproperties,1.TheapplicationofMD,Reportcontent,.,4,2.MDPotentialfunction,Pairpotential:Lennard-Jones、Morse,Multiplebodypotential,EAM、Finnis-Sinclair,ExtendedFSSMA-TB、SmoothedSMA-TBJohnson、Mishin、Zhou,Considertheangleeffect,MEAM/2NN-MEAMStillinger-Weber、TersoffBond-Orderpotential,.,5,二、Lammps软件的基本介绍,Lammps？,Large-scaleAtomic/MolecularMassivelyParallelSimulator,Advantage：Freeopensourcecode;canbemodifiedaccordingtoneedtoexpandthecalculationprocess（C+）Simulatethesolid,liquid,gasstateSimulatemillionsofparticlesConvenientparallelcomputing,.,6,Atomiccreation：(Command：read_data,lattice,create-atoms,delete,replicate)ReadtheatomfromthefileCreatesanatominoneormorelatticesDelete,copy,replace,Output：(Command：dump,restart)Theposition,speed,acceleration,energy,pressureoftheatom,.,7,4.LAMMPSexample,SimulationofSolidificationofCubyEAMPotentialCu：Latticestructure：FCC，4atoms/cellLatticeconstant：3.615Construct666supercellcells,864atoms，lx=ly=lz=21.69,.,8,VisualizationofAtomicStructures：Ovito,Ovitointerface,.,9,输出数据文件,StepTemperaturePotentialenergyTotalenergyPressureVolume,Scriptfile,Calculationresultanalysis,.,10,Glasstransitiontemperature：Tg1000K,eV/atomJ/mol,p0,H=U+pVU,.,11,Meansquaredisplacement(MSD):,Forbinaryalloys,theself-diffusioncoefficientDAandDBareobtainedfromtheslopeoftheMSD.AccordingtoDarkenslaw,theinterdiffusioncoefficientis：Dalloy=xBDA+xADB,.,12,.,13,PDF:,Thesecondpeaksplitsintotwopeaks,usuallyasignofamorphousformation,.,14,Simulationprocess：,EnterthefileRunOutputresultsVisualizationResultanalysis,Lamm