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Institute for Pure and Applied Mathematics, UCLANavigating Chemical Compound Space for Materials and Bio Design
Workshop III: Materials Design in Chemical Compound SpaceMay 2 - 6, 2011
Towards Materials AgeingA Case Study in Navigating Energy Landscapes
Sidney Yip
Nuclear Science and Engineering/Materials Science and Engineering
MIT
Connecting a few dots …
energy landscape view of time evolution of atomic system
An algorithm (metadynamics) to sample transition state pathway
Use TSP trajectories to explain the viscosity of glasses-- the nature of fragility in the glass transition
Other problems of slow dynamics (materials ageing) where atomistic simulations can elucidate the molecular mechanisms
Energy Landscape Perspective
Transition State Pathway Sampling (ABC)
TSP trajectories → Q(T)
Calculate viscosity of supercooled liquids
Connection with other materials ageing phenomena
creepcorrosionCement setting viscosity
Viscosities of vitrified liquids are in need of explanation by atomistic simulation
C. A. Angell, J. Phys. Chem. Solids 49 (1988)
Viscosity of a binary LJ model (Kob) calculatedusing a coarse-graining formulation based on TSP trajectory
A. Kushima et al, J Chem Phys 130 (2009)
]/)(exp[)( 0 TkTQT B
A. Kushima et al, J. Chem. Phys.130 (2009)
TSP trajectory analysis to obtain an effective temp-dep activation barrier Q(T)
Green-Kubo calculation using Network Model and TSP trajectories
A. Kushima et al, J. Chem. Phys.130 (2009), J. Li, Plos ONE 6, e17909 (2011)
SiO2
Saika-Voivid et al, Nature (2001)
Potential: Feuston and Garofalini, JCP (1988)
Horbach and Kob, Phys.Rev. B (1999)
C. A. Angell, J Phys Chem Solids 88 (1988)
A. Kushima et al, J. Chem. Phys.131 (2009)
Experimental test of predicted viscosity of SiO2
Disconnectivity Graphs of a fragile and strong glass former
A. Kushima, JCP 131 (2009) See Becker and Karplus, JCP 106 (1977), D. Wales (2006)
Potential energy landscape profiles (derived from TSP trajectories)
F. H. Stillinger, JCP 88 (1988)
A. Kushima et al., JCP 131 (2009)
Explanation of the signature behavior of glass transition-- revealing the underlying energy landscape that gives rise to the fragile temperature scaling of the shear viscosity η(T)
Mystery (mechanism) of the dynamical crossover(physical nature of fragility)
Transition from strong to fragile behavior with decreasing T signals the onset of deep local energy minimagiving rise to the sharp increase of Q(T)
contributors
Akihiro Kushima (MIT/UPenn)Xi Lin (BU)
Ju Li (UPenn/MIT)
John Mauro (Corning Research Center) Jacob Eapen (NCSU)Xiaofeng Qian (MIT)
Phong Diep (Corning Research Center)
R. L.Klueh, Int. Mat. Rev. 50, 287 (2005)
Creep deformation in steel P-91MD strain rates ~ 107 s-1 !
DOE Energy Innovation Hub in Nuclear Modeling and Simulation
CASL: Consortium for Advanced Simulationof Light Water Reactors
Core partnersOak Ridge National LaboratoryElectric Power Research InstituteIdaho National LaboratoryLos Alamos National LaboratoryMassachusetts Institute of TechnologyNorth Carolina State UniversitySandia National LaboratoriesTennessee Valley AuthorityUniversity of MichiganWestinghouse Electric Company
Vision: Create a predictive simulation capabilityfor a virtual LWR
Awarded May 28, 2010
CRUD deposition/growth (early stage) and CRUD-inducedlocalized corrosion (late stage) leading to clad cracking
Fe++ Ni++
Cement hydration (setting) is a ‘grand challenge’ to molecular simulation
ShearmodulusG* [Pa]
Ultrason measurement, w/c = 0.8 [Lootens 2004]C3S + H2O → C-S-H + Ca(OH)2
C3S = Ca3SiO3 C-S-H = CaO-SiO2-H2O
gelation
C-S-H precipitation
percolation/jamming
(CaO)1.65(SiO2)(H20)1.75
• green = inter-layer Ca• grey = intra-layer Ca• blue = oxygen• white = hydrogen
Binary Colloidal Model with sticky potentials [P. Monasterio, 2010]
Model is undergoing further development to incorporate
C-S-H nucleation/growth
Energy Landscape Perspective
Transition State Pathway Sampling (ABC)
TSP trajectories → Q(T)
Calculate viscosity of supercooled liquids
Connection with other materials ageing phenomena
creepcorrosionCement setting viscosity