Tight-binding density-functional theory -based

Although ab initio molecular orbital theory and density functional theory can be used to systematically improve the accuracy of X-Pol results for large systems, it is still impractical to use these methods to perform molecular dynamics simulations for an extended period of time. With increased computing power, this will become feasible in the future however, at present, it is desirable to use semiempirical molecular orbital models such as the popular approaches based on neglect of diatomic differential overlap (NDDO) or the more recent self-consistent-charge tight-binding density functional (SCC-method to model condensed-phase and biomacromolecules. 

Methods particularly devoted to biomolecular processes are more frequently used than multipurpose semi-empirical molecular orbital methods like AMI and PM3. Self-consistent-charge density functional theory based tight-binding (SCC-DFTB), an efficient method derived from density functional theory, is well adapted for QM/MM studies of biomolecular systems."... 

New versions of AMBER software support the option of allowing part of the system to be described quantum mechanically in an approach known as a hybrid (or coupled potential) QM/MM simulation. Both semi-empirical and the Density Functional Theory-based Tight Binding (DFTB) Hamiltonian can be used. The system may contain both two non-bonded parts and covalently bonded QM and MM sub-systems (Case et al. 2010). 

AMI Semiempirical Austin method 1 CSA Conformational space annealing DFT Density functional theory DFTB Density-functional-based tight binding EA Evolutionary algorithm... 

Within density-functional theory, a linear combination of overlapping non-orthogonal orbitals from first principles may be utilized to arrive at at full-potential local orbital (FPLO) method [213], and this k-dependent LCAO approach comes close to full-potential APW-based methods (see Sections 2.15.3 and 2.15.4) in terms of numerical accuracy, although FPLO is much faster simply because of the locality of the basis set. Even faster, due to a strongly simplified potential, is a parameter-free (density-functional) tight-binding method called TB-LMTO-ASA, derived through localization of a delocalized basis set (see Section 2.15.4). 

Bolton K et al (2009) Density functional theory and tight binding-based dynamical studies of carbon-metal systems of relevance to carbon nanotube growth. Nano Res 2(10) 774-782 Gavillet J et al (2001) Root-growth mechanism for single-wall carbon nanotubes. Phys Rev Lett 87(27) 275504-(4)... 

Zhechkov L, Heine T, Patchkovskii S, Seifert G, Duarte HA (2005) An efficient a posteriori treatment for dispersion interaction in density-functional-based tight binding. J Chem Theory Comput l(5) 841-847. doi 10.1021/ct050065y... 

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