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You can find a recording of the talk here: http://proteinsandwavefunctions.blogspot.com/2011/07/jans-talk-at-watoc-2011-part-2.html
Citation preview
Blurring the boundary between linear scaling QM, QM/MM and polarizable force fields
The Effec(ve Fragment Molecular Orbital Method
Jan H. Jensen, Casper Steinmann, Mikael Wisto1 Ibsen, Kasper Tho1e University of Copenhagen
Dmitri Fedorov AIST, Japan
1
The Fragment Molecular Orbital (FMO2) method (and most other fragmentaEon methods)
2
The Fragment Molecular Orbital (FMO2) method (and most other fragmentaEon methods)
Many-‐body PolarizaEon:
Monomer SCF in the Coulomb field of all other monomers
Iterated to self-‐consistency
3
The Fragment Molecular Orbital (FMO2) method (and most other fragmentaEon methods)
Non-‐Coulomb effects:
Dimer SCF in the Coulomb field of all other monomers
Iterated to self-‐consistency
4
The Fragment Molecular Orbital (FMO2) method (and most other fragmentaEon methods)
Coulomb effects:
Coulomb energy in the Coulomb field of all other monomers
5
The EffecEve Fragment Molecular Orbital (EFMO) method (Using ideas from the EffecPve Fragment PotenPal (EFP) method)
Monomer SCF in the gas phase
Extract mulPpoles and dipole polarizability
6
The EffecEve Fragment Molecular Orbital (EFMO) method (Using ideas from the EffecPve Fragment PotenPal (EFP) method)
Many-‐body polarizaEon
Computed classically using induced dipoles for enPre system
7
The EffecEve Fragment Molecular Orbital (EFMO) method (Using ideas from the EffecPve Fragment PotenPal (EFP) method)
Coulomb and Non-‐Coulomb effects
dimer SCF in the gas phase
8
The EffecEve Fragment Molecular Orbital (EFMO) method (Using ideas from the EffecPve Fragment PotenPal (EFP) method)
Coulomb effects
Computed using staPc mulPpoles
9
MP2 (DFT doesn’t scale well)
+ 0
10
Covalent FragmentaEon (ElectrostaPc screening crucial)
11
Implemented in GAMESS With gradients
Trp cage (20 residues) 2 residues/fragment
EFMO FMO2 Error in energy -‐4.3 6.4 kcal/mol
MP2/6-‐31G(d) gradient 314 409 minutes 20 cores (most Pme spent in MP2 dimers)
12
To Do
QM/”MM” PCM
Large parts of MM region o1en frozen
= Requires only monomer gas phase calculaPons
for that region =
Very fast
13
To Do
Flexible EFP/Polarizable “Force Field”
EEFMO = EI0
I
N
∑ + EIJ0 − EI
0 − EJ0 − EIJ
POL( )IJ
covalentdimers
∑
+ EIJES + EIJ
XR /CT + EIJDisp( )
IJ
N
∑ + EtotPOL
Important miscellanea
EFMO GUI: FRAGIT (Mikael Ibsen)
TS search algorithms (Kasper Tho1e)
14
Funding: EU (IRENE collab program)
Thank You!
QuesEons Now?
QuesEons Later?
Leave a comment on
hgp://proteinsandwavefuncEons.blogspot.com/2011/07/my-‐presentaPon-‐for-‐watoc-‐2011.html
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