Chapter 5 The AITRANSS package

The aitranss (ab initio transport simulations) package is a project under continuous development at the Institute of Nanotechnology of the Karlsruhe Institute of Technology (KIT), Germany, since 2002. In brief, when combined with FHI-aims, aitranss provides a post-processor module that enables, e.g., calculation of the electron transport characteristics of molecular junctions based on a Landauer formalism in a (non-equilibrium) Green’s function formulation.

Currently, the version of the code accessible to FHI-aims users is limited to computation of the ballistic (Landauer-Büttiker) transmission function and partial atom-projected density of states. According to current planning advanced options, e.g., out of equilibrium transport response, will be available in the future releases.

A discussion of the underlying physical formalism and details of the implementation are described in the references [15, 315, 20]:

A. Arnold, F. Weigend, and F. Evers, "Quantum chemistry calculations for molecules coupled to reservoirs: Formalism, implementation, and application to benzenedithiol." J. Chem. Phys. 126, 174101 (2007).

J. Wilhelm, M. Walz, M. Stendel, A. Bagrets, and F. Evers, "Ab initio simulations of scanning-tunneling-microscope images with embedding techniques and application to C58-dimers on Au(111)." Phys. Chem. Chem. Phys. 15, 6684 (2013).

A. Bagrets, "Spin-polarized electron transport across metal-organic molecules: a density functional theory approach." J. Chem. Theory Comput. 9, 2801 (2013).

Please, cite the above works together with FHI-aims publications, when using aitranss.

For questions and bug reports, contact Alexej Bagrets (Alexej.Bagrets@kit.edu).