Density-functional based tight-binding

Koskinen, P., Hakkinen, H., Seifert, G Sanna, S., Frauenheim, Th. and Moseler, M. (2006) Density-functional based tight-binding study of small gold clusters. New Journal of Physics, 8, 9—11. 

As a consequence of the size limitations of the ab initio schemes, a large number of more-approximate methods can be found in the literature. Here, we mention only the density functional-based tight binding (DFTB) method, which is a two-center approach to DFT. The method has been successfully applied to the study of proton transport in perov-skites and imidazole (see Section 3.1.1.3). The fundamental constraints of DFT are (i) treatment of excited states and (ii) the ambiguous choice of the exchange correlation function. In many cases, the latter contains several parameters fitted to observable properties, which makes such calculations, in fact, semiempirical. 

Frauenherm, T.. Seifert, G., Elstner, M., Hajnal, Z., Jungnickel. G.. Porezag. D.. Suhai. S.. and Scholz. R. 2000. A Self-consistent Charge Density-functional Based Tight-binding Method for Predictive Materials Simulations in Physics, Chemistry and Biology , Phys. Stat. Sol. B. 217. 41. 

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

Frauenheim T, Seifert G, Elstner M, Hajnal Z, Jungnickel G, Porezag D, Suhai S, Scholz R (2000) A self-consistent charge density-functional based tight-binding method for predictive materials simulations in physics, chemistry, and biology (2000) Physica Status Solid B 217 41-62 Espan ol P (1998) Fluid particle model. Phys Rev E 57 2930-2948... 

Density Functional-Based Tight Binding DFTB. 125... 

The resulting density functional-based tight binding (DFTB) method works well for homo-nuclear systems, where the charge transfer between the atoms in the system does not occur or is... 

A self-consistent charge density functional based tight binding (SCC-DFTB) method was used for the calculations of the geometries, electronic... 

Finally, metallic allotropes with higher coordination numbers have been studied [39,51] and found to be well removed in enthalphy from four-fold coordinated structures below a pressure of 10 Mbar. Here, we report on the geometric optimization and doping properties of the recently proposed purely sp bonded carbon phases [15] and a propotype zeolite structure (sp bonded) called melanoph-logite using the density-functional based tight-binding method (DF-TB) [52,53]. 

Calculation of Si Chemical Shifts Using a Density-Functional Based Tight-Binding Scheme. ..324 Marc Milbradt, Heinrich Marsmann, Thomas Heine, Gotthard Seifert, Thomas Frauenheim... 

A compromise between computational effort and accuracy can be readied within an approximate KS-DFT scheme - a density functional based tight-binding (DFTB) method. This approximation assumes very strong atomic potential so that different atomic orbitals barely overlap. It can be considered the analog of the standard linear combination of atomic orbital (LCAO) approach with an LCAO representation of the KS orbitals. Like the LCAO approach, the atomic locations can be specified arbitrarily, so the method can be applied to nonperiodic (noncrystalline) materials. The fundamental step of the DFTB... 

Oliveira, AF., Seifert, G., Heine, T. Duarte, H.A. (2009) Density-functional based tight-binding An approximate dft method. Journal of the Brazilian Chemical Society, 20, 1193-1205. 

Somewhat removed is the density functional based tight-binding method (DFTB), which is based on a second-order expansion of the Kohn-Sham total energy, employing a self-consistent redistribution of Mulliken charges (SCC-DFTB) (Elstner et al. 1998). It also employs dispersion corrections similar to the DFT-D method and has successfully been applied, e.g., to nuclear-base stacking problems (Elstner et al. 2001). 

Oliveira AF, Seifert G, Heine T, Duarte HA (2009) Density-functional based tight-binding an approximate DFT method. J Braz Chem Soc 20 1193-1205. doi 10.1590/S0103-50532009000700002... 

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... 

Kruger T et al (2005) Validatitm of the density-functional based tight-binding approximation method for the calculation of reaction energies and other data. J Chem Phys 122 5... 

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