In this paper, we present a problem solving environment (PSE) for the large scale electronic structure calculations based on the O(N) tight binding method. We have developed a simulator named Fujitsu Tight binding Simulator (FuTiS). By implementing the O(N) method on parallel computers and introducing a common interface, we can perform the electronic structure simulations involving more than a ...

The NRL developed tight-binding method has been very successful in describing the properties of nonmagnetic elemental metals and semiconductors with accuracy comparable to first-principles methods. In this article we discuss extensions of the method to magnetic systems. We first show that the method correctly predicts equilibrium ground state structures, elastic constants, and phonon frequencie...

A new general tight-binding total energy (TBTE) method is presented that accurately predicts energy diierences caused by small perturbations such as those occurring in the evaluation of elastic constants and phonon spectra as well as energy diierences from large changes in structure such as structural energy diierences, equations of state, and defect energies. Unlike other quantitative TBTE mod...

A nonadiabatic molecular dynamics is implemented in the framework of the time-dependent density functional tight binding method (TDDFTB) combined with Tully's stochastic surface hopping algorithm. The applicability of our method to complex molecular systems is illustrated on the example of the ultrafast excited state dynamics of microsolvated adenine. Our results demonstrate that in the presenc...

O método DFTB, bem como a sua extensão com carga corrigida auto-consistente SCC-DFTB, tem ampliado a faixa de aplicações das ferramentas teóricas com fundamentos bem estabelecidos. Como uma aproximação do método do funcional de densidade, o método DFTB mantém aproximadamente a mesma precisão, mas com custo computacional menor, permitindo a investigação da estrutura eletrônica de sistemas grande...

The Hubbard-type tight-binding ~TB! Hamiltonian is generalized to incorporate effects of charge transfer efficiently into the TB ~Slater-Koster-type! parameters. The generalization is such that charge transfer as well as Madelung-type interactions are included in a self-consistent manner. In particular, the intrasite Coulomb interactions of our Hubbard Hamiltonian are calculated from the chemic...

We have developed an order-N method to calculate the total energy and atomic forces for a nonorthogonal tight-binding Hamiltonian. We have first confirmed the validity of our approach by comparing our results with the exact calculation for a small silicon cluster. The efficiency of our approach for a large system is demonstrated by determining the equilibrium configuration of a Si1000 cluster u...