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http://staff.aist.go.jp/t-ozaki/. ABRED (by Ozaki). Pseudopotential Localized basis set (LCAO) charge: uniform grid --- similar to SIESTA But basis function optimization stable order-N algorithm. Making PseudoAtomic orbitals (PAO). TM/BHS PS. A wall to make PAOs confined.
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http://staff.aist.go.jp/t-ozaki/ ABRED (by Ozaki) • Pseudopotential • Localized basis set (LCAO) • charge: uniform grid • --- similar to SIESTA • But • basis function optimization • stable order-N algorithm
Making PseudoAtomic orbitals (PAO) • TM/BHS PS A wall to make PAOs confined continuous upto 2nd deriv. PAO PS Defs. four s basis func.= s4 • Scalar rel., Log-deri tune OK From http://staff.aist.go.jp/t-ozaki/
PAO: basis set rC rC rC rC
Is DZP basis set enough? (DZP=s2p2d1) Basis functions of dimer molecules 4% 3% s1p1 →s5p5→s5p5d5 s1p1 →s5p5→s5p5d5→s5p5d5f5 From http://staff.aist.go.jp/t-ozaki/
More orbital sets→ more accurate, but heavier calculations • recombination of the basis functions Optimized basis set s1p1→s6p6→s6p6d6 s1p1→s2p2d2 Ozaki, to be appeared in PRB
PSs and PAOs X: available From http://staff.aist.go.jp/t-ozaki/
At zero bias, what can we do from the results of the periodic systems? Carbon nanotubes =results(periodic) →<yi|H|yj> and <yi|S|yj> are known.