Recap on Basis Sets
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Recap on Basis Sets Pablo Ordejon ICMAB-CSIC
description
Recap on Basis Sets. Pablo Ordejon ICMAB-CSIC. Basis Sets in SIESTA. Generated from the solution of the FREE ATOM (with the pseudopotential) Finite range: (r) = 0 for rr c (boundary condition) Energy shift by confinement: shorter r c means higher energy E. - PowerPoint PPT Presentation
Transcript of Recap on Basis Sets
Recap on Basis Sets
Pablo OrdejonICMAB-CSIC
Basis Sets in SIESTA
• Generated from the solution of the FREE ATOM (with the pseudopotential)
• Finite range: (r) = 0 for rrc (boundary condition)
• Energy shift by confinement: shorter rc means higher energy E
Single- (SZ)and
First- in MZ bases
Shape of the orbitals: rc
O 2s orbital
rc = 3 a.u.
E = 500 meV
rc = 4.5 a.u.
E = 10 meV
Shape of the orbitals: rc
Fe 3d orbital
Fe 4s orbital
rc = 6 a.u.
E = 400 meV
rc = 10 a.u.
E = 5 meV
Energy vs. rc - Molecules
H2O
Energy vs. rc - Solids
Bulk Fe
Second- in DZ bases
Split Valence
Gaussians
SZ
DZ
Split Valence
SIESTA
SZ
DZ
Shape of the orbitals: DZ
O 2s orbital
E = 10 meV
SplitNorm 0.15
Shape of the orbitals: DZ
O 2s orbital
E = 500 meV
SplitNorm 0.15