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:

Slides:



Advertisements
Similar presentations
Basis Sets for Molecular Orbital Calculations
Advertisements

Javier Junquera Exercises on basis set generation Full control on the definition of the basis set functions: the PAO.Basis block.
Javier Junquera Exercises on basis set generation Control of the range of the second-ς orbital: the split norm.
Javier Junquera Exercises on basis set generation Control of the range: the energy shift.
Take-home postcard. Basis set: Atomic orbitals s p d f SIESTA: Strictly localized (zero beyond cut-off radius)
Systematics for realistic proyects: from quick & dirty to converged calculations José M. Soler and Alberto García.
Pseudopotentials and Basis Sets
VSEPR Theory Geometry of Molecules.
Transport Calculations with TranSIESTA
Metallic Bonds A Closer Look. Metallic Bonds Are formed when metallic atoms overlap the orbitals of loosely held valence electrons. Metallic bonds are.
Javier Junquera Atomic orbitals of finite range as basis sets.
Atomic spectra are a result of energy level diagrams - quantum theory.
How to optimize automatically the parameters that determine the quality of the basis Javier Junquera Alberto García.
METALLIC BOND bond found in metals; holds metal atoms together very strongly.
The Nature of Covalent Bonding Objectives: 1. Describe the characteristics of a covalent bond. 2. Describe the difference between polar and nonpolar covalent.
Javier Junquera Exercises on basis set generation Increasing the angular flexibility: polarization orbitals.
Dot Structures.
Binding Energy Per Nucleon The binding energy per nucleon of a nucleus is the binding energy divided by the total number of nucleons in the nucleus Binding.
Ionic and Covalent Compounds. How many valence electrons do atoms need in the highest energy level to be stable? 8.
Menu Substances appear coloured when visible light energy is absorbed by an atom, ion or molecule.
R. Martin - Pseudopotentials1 African School on Electronic Structure Methods and Applications Lecture by Richard M. Martin Department of Physics and Materials.
Conductors - Insulators What causes charge? How does charge move ?
Université de Liège Numerical Atomic Orbitals: An efficient basis for Order-N ab-initio simulations Javier Junquera.
Section 5.3 Quantum numbers and Atomic Orbitals Quantum numbers are numbers that specify the properties of atomic orbitals and of the electrons in that.
- Compute and analyze the band structure of an ionic solid
Molecular Orbital Energy Diagrams (16.7) MO energy diagrams are useful in that they show how atomic orbitals from different atoms may combine to molecular.
Bond Types. Bond Types: At the conclusion of our time together, you should be able to: 1. Identify 5 different bond types 2. Explain each bond type 3.
Optimization of Numerical Atomic Orbitals
Valence Electrons 9/8/2015.
Linear scaling solvers based on Wannier-like functions P. Ordejón Institut de Ciència de Materials de Barcelona (CSIC)
Introduction to the SIESTA method SUMMER SCHOOL ON COMPUTATIONAL MATERIALS SCIENCE University of Illinois at Urbana-Champaign, June 13-23, 2005 Some technicalities.
Quantum Mechanical Model Or…”Electron Cloud Model” Electrons move freely within “clouds” (called orbitals) not just restricted to orbits. [
Chapter 2 Of Atoms and Molecules: Chemistry Basics.
Start. Technische Universität Dresden Physikalische Chemie Gotthard Seifert Tight-binding Density Functional Theory DFTB an approximate Kohn-Sham DFT.
Origin of energy band formation:
Atoms and Molecules The stuff life is made of.. Atoms Crucial points: An atom is the smallest unit of an element. Atoms are made up of electrons, protons,
Unit 4: Metallic Bonding. Metallic Bonds are… How metal atoms are held together in the solid. Metals hold on to their valence electrons very weakly. Think.
Chem. 1B – 11/17 Lecture.
Ionic bonding and compounds
Band structure of a cubic perovskite oxide:
Atomic orbitals of finite range
Ch 9 – Covalent Bonding: Orbitals
Orbitals s orbitals are spherically shaped
Molecular Shape (Geometry)
Electron Dot Structure or Lewis Dot Structures
Electronic Structure and First Principles Theory
Ch 9 – Covalent Bonding: Orbitals
Notes 5 - Periodic Table Families & Groups
Lecture 8: Volume Interactions
Follow along and fill in the missing information on your sheet.
Chapter – 1 Atomic Spectroscopy
Molecules 3.3.
Valence Electrons Cornell Notes.
Molecules 3.3.
Molecules 3.3.
Lecture 8A - Formation of Covalent (Molecular) Compounds
Electrons & Atoms.
Lecture 8: Volume Interactions
Which kind of electromagnetic radiation has the least amount of energy? RADIO WAVES.
+ + - If it loses an electron the atom now has one too many protons in the nucleus. The atom now has a positive charge and is called an ION. This happens.
Molecular Orbitals Two interacting orbitals make two new orbitals. Using a 1s orbital on two H atoms: anitbonding orbital = higher energy bonding orbital.
Electron configuration explained
Representations of the Nuclear Potential
Valence Electrons Cornell Notes.
Covalent Bonding.
VSEPR Theory Geometry of Molecules.
Hybridization.
Electron Configuration
Electron Dot Structure or Lewis Dot Structures
Presentation transcript:

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 r  r c (boundary condition) Energy shift by confinement: shorter r c means higher energy   E

Single-  (SZ) and First-  in MZ bases

Shape of the orbitals: r c O 2s orbital r c = 3 a.u.  E = 500 meV r c = 4.5 a.u.  E = 10 meV

Shape of the orbitals: r c Fe 3d orbital Fe 4s orbital r c = 6 a.u.  E = 400 meV r c = 10 a.u.  E = 5 meV

Energy vs. r c - Molecules H2OH2O

Energy vs. r c - 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