Quantum Chemistry

  1. Electronic Structure Calculations
    1. Ab Initio Methods
      1. Hartree-Fock Theory
        1. Self-Consistent Field Method
          1. Advantages and Limitations
            1. Basis Set Choice
              1. Restricted vs. Unrestricted Hartree-Fock
              2. Post-Hartree-Fock Methods
                1. Configuration Interaction (CI)
                  1. Full CI vs. Truncated CI
                    1. Excitation Levels (e.g., CIS, CISD)
                      1. Scaling and Computational Cost
                      2. Møller-Plesset Perturbation Theory (MPPT)
                        1. MP2, MP3, MP4 Methodologies
                          1. Applicability and Convergence Issues
                            1. Comparison with other methods
                            2. Coupled Cluster Theory
                              1. Coupled Cluster Singles and Doubles (CCSD)
                                1. CCSD with Perturbative Triples Correction (CCSD(T))
                                  1. Applications in Highly Correlated Systems
                                    1. Computational Complexity and Resource Usage
                                2. Density Functional Theory (DFT)
                                  1. Exchange-Correlation Functionals
                                    1. Local Density Approximation (LDA)
                                      1. Generalized Gradient Approximation (GGA)
                                        1. Hybrid Functionals
                                          1. B3LYP and PBE0 Specifics
                                          2. Challenges in Functional Selection
                                            1. New Functional Developments
                                            2. Kohn-Sham Equations
                                              1. Single-Particle Approximation
                                                1. Solving Kohn-Sham Equations
                                                  1. Relation to Hartree-Fock Theory
                                                    1. Self-Interaction Error and Corrections
                                                  2. Semi-empirical Methods
                                                    1. Huckel Theory
                                                      1. Application to Conjugated Systems
                                                        1. Band Structure Calculations
                                                          1. Limitations and Simplifications
                                                          2. Extended Huckel Theory
                                                            1. Overlap and Coulomb Matrices
                                                              1. Comparison with Ab Initio Methods
                                                                1. Practical Applications in Solid State Chemistry
                                                                2. Other Semi-empirical Methods
                                                                  1. MNDO, AM1, PM3, and Their Improvements
                                                                    1. Applicability to Large Systems
                                                                      1. Trade-offs Between Speed and Accuracy
                                                                    2. Basis Sets
                                                                      1. Purpose and Construction
                                                                        1. Minimal Basis Sets
                                                                          1. STO-3G and Its Applications
                                                                          2. Split-Valence Basis Sets
                                                                            1. Pople and Dunning Basis Sets
                                                                              1. Influence on Computational Cost
                                                                              2. Polarization and Diffuse Functions
                                                                                1. Augmentation for Excited States
                                                                                  1. Importance for Anionic Systems
                                                                                2. Numerical Methods
                                                                                  1. Matrix Diagonalization Techniques
                                                                                    1. Eigenvalue Problems in Quantum Chemistry
                                                                                      1. Direct and Iterative Diagonalization Methods
                                                                                      2. Grid-based Methods
                                                                                        1. Real-Space Grids vs. Fourier Grids
                                                                                          1. Applications in DFT
                                                                                            1. Challenges in High-Precision Grids
                                                                                            2. Monte Carlo Simulations
                                                                                              1. Random Sampling Techniques
                                                                                                1. Quantum Monte Carlo (QMC) Methods
                                                                                                  1. Comparison to Deterministic Algorithms
                                                                                                2. Challenges in Electronic Structure Calculations
                                                                                                  1. Scaling and Computational Cost
                                                                                                    1. Parallel Computation Strategies
                                                                                                      1. Distributed Computing Environments
                                                                                                      2. Accuracy vs. Efficiency Trade-offs
                                                                                                        1. Balance in Method Selection
                                                                                                          1. Case Studies and Examples
                                                                                                          2. Emerging Methods and Technologies
                                                                                                            1. Quantum Computing in Electronic Structure
                                                                                                              1. Machine Learning Assisted Potential Surfaces
                                                                                                                1. Development of New Algorithms