SEARCH Articles Figures Tables Adiabatic approximation autocorrelation function Adiabatic approximation functions Adiabatic approximation wave function Analytic approximating functions Approximate Distribution Functions Approximate Relationships Between Viscoelastic Functions Approximate density function Approximate exchange functionals Approximate functionals Approximate transfer functions Approximate treatment, partition function Approximating Complicated Functions Approximation function Approximation function Approximation of functions Approximation of the process transfer function Approximations by Piecewise Smooth Functions Approximations for Trigonometric Functions Approximations for the direct correlation function Approximations in Relativistic Density Functional Theory Approximations radial functions Approximations to the Many-Electron Wave Function Autocorrelation function approximations Born-Huang approximation wave function Boundary approximating function selection Calculations from experimental functions approximate Central field approximation, angular momentum and spherical functions Correlation into an Approximate Wave Function Current approximation function Delta-function approximation Density functional approximation Density functional generalized gradient approximation Density functional theory Kohn-Sham approximation Density functional theory approximate treatment Density functional theory approximations Density functional theory generalized gradient approximation Density functional theory generalized random phase approximation Density gradient approximation-type correlation functional Determination of Spectra from Viscoelastic Functions Using First-Order Approximations Dirac delta function approximation Discrete Approximation of Continuous Transfer Functions Domain Partition and Linear Approximation of the Yield Function Energy distribution functions condensation approximation Energy from an Approximate Wave Function Exact and Approximate Wave Functions Examples of analytic approximating functions Exchange correlation functionals, local density approximations Exchange-correlation functional generalized gradient approximation Exchange-correlation functional local density approximation Explicit calculation of compressible flow using approximating functions Explicit using approximating functions Fukui function finite difference approximations Function approximation method Functional Generalized Gradient Approximation Functional Thomas-Fermi approximation Functional approximation Functional gradient approximation Gaussian function approximation Generalized gradient approximation correlation wave functions Generalized gradient approximations exchange correlation functionals Genetic function approximation Genetic function approximation (GFA Genetic function approximation analysis Genetic function approximation regression Genetic function approximation selection Green function fixed-node approximation Group function approximation Hartree-Fock approximation trial wave function Hartree-Fock approximation wave function High frequency (WKBJ) approximation for the Greens function Jacobs Ladder of Density Functional Approximations Langevin function approximation Local spin-density approximations hybrid exchange functionals Many-electron wave functions atomic orbitals approximation Mathematical methods approximating functions Method approximate density functional theory Molecular function approximation Nonlinear response function approximate expression Numerical methods approximation function Orbital functionals and other nonlocal approximations hybrids, Meta-GGA, SIC, OEP, etc Pair correlation function approximation Parabola function approximation Partition function adiabatic approximation Partition functions approximate Performance of Approximate Functionals A Few Phase-integral approximation generated from an unspecified base function Rational function approximation Response function approximate expression Response function approximating Size of errors using approximating functions Spatial function symmetry orbital approximation Spectral functions librator approximations Strength function approximate computation Tamm-Dancoff approximation functions The Current Approximation Function The Quest for Approximate Exchange-Correlation Functionals Two-Point Approximate Orbital-Free Kinetic Energy Functionals Viscoelastic functions approximate Wave function Born-Oppenheimer approximation Wave functions, approximate Wave functions, approximate correct zeroth-order Wave functions, approximate determinant-type Wave functions, approximate hydrogenlike Wave functions, nonadiabatic quantum approximation