Tight-binding approach to time-dependent density-functional response theory
نویسندگان
چکیده
In this paper we propose an extension of the self-consistent charge-density-functional tight-binding ~SCCDFTB! method @M. Elstner et al., Phys. Rev. B 58, 7260 ~1998!#, which allows the calculation of the optical properties of finite systems within time-dependent density-functional response theory ~TD-DFRT!. For a test set of small organic molecules low-lying singlet excitation energies are computed in good agreement with first-principles and experimental results. The overall computational cost of this parameter-free method is very low and thus it allows us to examine large systems: we report successful applications to C60 and the polyacene series.
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