Recent progress in the nanoscience requires the reconsideration of the conventional understanding of the material properties with help of the computational materials science and the state-of-the-art computer technologies. Our project is aimed to obtain the theoretical understanding and predictions of the material properties in terms of the quantum mechanical symmetry which governs the nanoscale properties and the non-empirical electronic theory.
In order to perform reliable simulations on very large systems, such as nano-structured materials, nano-scaled catalysts, and bio-systems, we have been developing a linear-scaling DFT method. With this method, we can employ DFT calculations on systems containing more than tens of thousands of atoms. Electron transport properties of nano-structures such as atomic wires, molecular wires and defects in thin films have attracted much attention recently. We develop the first-principles calculation method to investigate the transport properties of such nano-structures.