SEARCH Articles Figures Tables Approximate Molecular Orbital Theory for 4-Electron 3-Centre Bonding Units Approximate molecular orbital Approximate molecular orbital methods Atomic orbital Huckel approximation Atomic orbitals approximate relative energies Atomic structure orbital approximation Beyond the Orbital Approximation Bond Orbital Mode Approximation Born-Oppenheimer approximation molecular orbitals Comparison of Available Orbital-Dependent Approximations for Ec Computational quantum mechanics approximate orbital theories Electron excitation probability atomic orbitals approximation Electron repulsion orbitals, an approximation Electrons orbital approximation Frontier orbital approximation Frontier orbital approximation HOMO-LUMO interactions Frontier orbital approximation limitations Frozen orbital approximation Frozen-orbital approximation excitation energies Hartree-Fock approximation occupied spin orbitals Higher-order orbital approximations Higher-order orbital approximations configurations Integral approximation, semiempirical molecular orbital theory Linear Combination of Atomic Orbitals Approximation Linear combination of atomic orbitals LCAO) approximation Localised molecular orbital approximation Localized Orbitals for Valence Bands LCAO approximation MNDO approximation, semiempirical molecular orbital theory Many-electron wave functions atomic orbitals approximation Mean-Field Approximations for Spin-Orbit Interaction Molecular orbital LCAO approximation Molecular orbital Pariser-Parr-Pople approximation Molecular orbital approximation Molecular orbital calculations Huckel approximations Molecular orbital linear combination atomic orbitals approximation Molecular orbital method Hiickel approximation Molecular orbital methods LCAO approximation Molecular orbital theory Hartree-Fock self-consistent field approximation Molecular orbital theory approximate Molecular orbital theory approximate methods Molecular orbital theory approximation Molecular orbital theory tight-binding approximation Orbital approximate theories Orbital approximation Orbital approximation Orbital functionals and other nonlocal approximations hybrids, Meta-GGA, SIC, OEP, etc Orbital properties Hiickel approximations Polarized-orbital approximation Self-consistent field orbital approximation method Generating Semiempirical molecular orbital approximations Simple Hiickel molecular orbital theory approximations Slater-type orbital approximation Spatial function symmetry orbital approximation Spin-orbit interaction approximation Spin-orbit mean-field approximation The LiH molecule approximate molecular orbital calculations The Orbital Approximation Helium The Orbital Approximation for Lithium The Wavefunctions of Many-Electron Atoms Can Be Described to a Good Approximation Using Atomic Orbitals The orbital approximation Tin Orbitals and the Atomic Sphere Approximation Two-Point Approximate Orbital-Free Kinetic Energy Functionals Variation method orbital approximation