Modelling of Materials and Nanotechnologies:

1
Modelling of Materials and Nanotechnologies From
Ab Initio to Macro-Simulations

• Dr. Jérôme Cornil

• Jerome.Cornil_at_umons.ac.be

Laboratory for Chemistry of Novel
Materials University of Mons, Belgium
Industrial Technologies, June 2012, Aarhus
2
Multiscale Modelling
ms to ks
104-106
100-104 / fs to ns
10-100
http//www.cse.sc.edu/heyden/Multi-ScaleModelling
.html
3
Quantum-Chemistry
Key quantity Wavefunction
Time-independent Schrödinger equation
H ? E ?
Approximations
F ?i (r) ?i ?i (r)
Hartree-Fock equation
Averaged electronic interactions ?
Correlation error E0 EHF
4
Quantum-Chemistry
Post-Hartree Fock methods
Perturbative
Variational
Configuration Interaction (CI)
Möller Plesset (MP2, MP3,..)
Very time consuming ?
?CI C0 ?SCF ? CJ ?Ja?b ? CK ?Ka?b
...
c?d
J
K
Truncations needed ?
Access to excited states ?
Coupled Cluster (CC)
CASSCF
5
Density Functional Theory (DFT)
Key quantity Electronic density
Hohenberg-Kohn functional
E0 ?0 FHK ?0 ? ?0(r ) Vext dr
F ? TS ? J ? EXC ?
Exchange-correlation energy
fKS ?i ?i ?i
Kohn-Sham equation
Need to find expressions for EXC ?
Self-interaction error ?
Access to excited states (TD-DFT) ?
6
DFT and HF
- Explicit account of electrons ?
- Limitation in the size of the system (a few
hundred atoms) ?
Semi-empirical Hartree-Fock techniques
- Poor description of van der Waals interactions
?
- Use of Periodic Boundary Conditions (PBC) ?
Slab approach
CH3S on gold
Gaussian, Turbomole, VASP, SIESTA, DMOL, CRYSTAL,
MOPAC, ABINIT
7
Phenomenological Models
Vibrations
Sites
Coupling
- Charge transport
Tight-binding models (Tight-binding DFT)
8
Force Field Calculations
E
Bending
Stretching
Out-of-plane
Torsions
H-bonds
Non bonded interactions
(van der Waals, Coulombic)
9
Force Fields
Parameterized from quantum-chemical calculations
and/or experimental data
Stretching
Bending
Vb kb (? ?0)2
Vs ks (r r0)2
Harmonic approximation
van der Waals
Coulomb
qi qj
Vc ?
Vw (Aij / r12 Bij / r6)
4 ? ?0 ?r r
Lennard-Jones potential
10
Force Fields
- No explicit account of electrons ?
- Parameterization from QC calculations or
experimental data ?
- Large size of the systems (many thousands) ?
- Explicit term for vdW interactions ?
Organic
Specific force fields ?
MM2, MM3
UFF (Universal Force Field)
COMPASS (Condensed-phase Optimized Molecular
Potentials for
Atomistic Simulation Studies)
Biologic (proteins, nucleic acids)
AMBER (Assisted Model Building with Energy
Refinement)
CHARMM (Chemistry at HARvard using Molecular
Mechanics)
Reliable description of H-bonds
Materials Studio, GROMACS, NAMD, TINKER, LAMMPS
11
Molecular Simulations
Molecular Mechanics
Molecular Dynamics
E(x)
E(x)
x
x
Search for equilibrium structures
Exploration of the conformational space
Simulated Annealing Monte Carlo
PBC Available
Quantum dynamics Car Parrinello (CPMD)
12
QM/MM
- Embedding of a quantum part in a classical
medium
- Interest in using polarizable force field
T. Van Voorhis and co, Acc. Chem. Res. 7, 43, 995
13
Coarse-Graining
Atomistic description ? Effective interaction
potentials
Key role of the parameterization ?
Claudio Zannoni, University of Bologna
14
Coarse-Graining
C. Zannoni, J. Mater. Chem., 11, 2637, 2001
15
Kinetic Monte Carlo (KMC)
?ij
- Random choice of the destination
i
j
- Probability of transfer
- Random number between 0 and 1 ?
If ? ? Pij, the transfer is accepted with a time
?ij-1
If ? ? Pij, the transfer is not accepted
16
Continuum Models Device Modelling

• Tools to solve classical differential equations
  fed with input parameters coming
• from experiment or molecular simulations
  (Finite Element Methods FEM)

Comsol, Abaqus
- Specific to the applications (fluid, charges)
- Charges ? Drift-diffusion model
Charge density profile !!
- Fluid ? Navier-Stokes equation
Fluid density profile !!
- Structural mechanics
- Implicit account of chemistry concepts
17
AMCOS 233502 Materials as CO2 removers
Zeolite framework for selective sorption of CO2
Force Field (Dreiding)
Molecular Dynamics, Monte Carlo
DFT (partial charges)
Amount of gas sorbed (isotherms)
CO2 diffusion
J. Mater. Chem., 2010, 20, 7676-7681
18
HYMEC 263073
Non volatile hybrid memories
- Gold nanoparticles in organic semiconductors
- Switch via charging of the nanoparticles
Quantum-chemistry (Electronic structure of the
NPs and molecules)
Kinetic Monte Carlo or Master Equation (mobility)
Drift Diffusion Model (I/V characteristics)
19
MAHEATT 227541
Search for new cathode materials in Li-ion
batteries for increased storage
DFT Structure and stability of the materials
Intercalation and deintercalation of Li
DFT - MD
Li-ion mobility
20
MODIFY 228320
Stress induced mechanical properties of
soft-based adhesives (acrylic polymers)
Force field (interaction polymer/substrate
formation of H bonds)
Coarse graining (interaction between particles)
Finite element (bulk rheological properties
debonding mechanisms)
21
MORDRED 261868
Nanoelectronics
Random defects trapped charges
DFT
22
MULTIHY 263335
DFT (energy barriers / binding energies)
Tight binding ? Grain boundaries
Kinetic Monte Carlo (hydrogen diffusion as a
function of defect, T, stress)
Finite Element Method (macroscopic model for
hydrogen diffusion)
23
HYPOMAP 233482
New materials for hydrogen storage / proton
exchange membranes
DFT Chemisorption / physisorption of H2 in metal
hydrides and MOFs
Proton diffusion rates
DFTB up to 1000 10000 atoms
24
POCO 213939
Interactions of functionalized carbon nanotubes
with polymer matrices
Force field calculations
Interaction energies Pull-out energy
FEM
Mechanical properties
25
ADGLASS 229205
Adhesion and cohesion at interfaces in high
performance glassy systems
Anti-adherent properties for proteins
Adhesion between glassy SiO2 and crystalline TiO2
for solar collectors
Hybrid quantum-mechanical atomistic modelling
Quantum chemistry involved for the formation of
chemical bonds, proton transfer
Model development !
26
Dynamag 233552 and Magnonics 228673
Spin wave spectra and dispersion
DFT (Exchange energy)
Magnonic devices
Finite Element Micromagnetic package
New models for new physics !!
27
MINOTOR 228424
Self-Assembled Monolayers
HS-C16H33
20 nm metal 20 nm metal HS-C16H33 20 nm metal
HS-C2H4C8F17
HS-C2H4C8F17
Work function eV
Au Ag metal (SAM)

Tuning of injection barriers
Bert de Boer et al., Adv. Mater., 2005, 17, 621
28
Theoretical Methodology
CH3S
?? (bridge) -1.19 eV
?? (fcc) -1.52 eV
SIESTA DFT GGA (PBE)
29
Perspectives
- Linear scaling
- Dispersion forces at the quantum level
- Hybrid approaches QM/MM
- Polarizable force fields, reactive force fields
- More links between the atomistic and
macroscopic world
- Automatized procedure for multiscale modelling
30
MMM_at_HPC e-infrastructure
Proposal , pp. 5-8
31
Partners
Participant Acronym Country
Karlsruhe Institute of Technology KIT Germany
Commissariat à l'énergie atomique CEA France
CINECA Bologna CIN Italy
CSC - IT Center for Science CSC Finland
Korea Institute of Science and Technology KIST Korea
Sony SONY Germany
Science and Technology Facilities Council STFC UK
University of Mons Umons Belgium
University of Patras UPA Greece
Nokia
CSC
STFC
KIT
UMons
Sony
CEA
CIN
UPA
www.multiscale-modelling.eu
32
Application Example

• Film deposition (or MD)
• Generate disordered film morphologies
• QM calculations of hopping sites
• Calculate HOMO, LUMO, LUMO1 etc energies.
• Electronic couplings reorganization energies
• Calculate charge hopping rates
• Kinetic Monte Carlo (KMC)
• Calculate charge (electron-hole) mobility
• Calculate current density

Workflow
J. J. Kwiatkowski, J. Nelson, H. Li, J. L.
Bredas, W. Wenzel, and C. Lennartz, Phys. Chem.
Chem. Phys., 2008, 10, 18521858.
33
Graphical User Interface for individual codes and
entire workflows
Gridbeans
UNICORE Rich Client
Workflow
Embedded visualisation with Jmol
34
Control flow Example
35
Coverage of different scales
continuum model (FEA) coarse-grained model (CG) Atomistic model(MM) QM model(QM)
Elmer ToFeT (KMC) DEPOSIT MOPAC
FEAP End-bridging MC LAMMPS TURBOMOLE
Transporter DL_POLY BigDFT