First principles calculation of the electrical properties of single molecules.

K. Stokbro
Nanoscience Center HCØ, DK

Keywords: quantum transport, nano electronics, first principles calculations

Abstract:
Recent developments in applying quantum chemistry methods to electrical transport, have made it possible to calculate the current/voltage characteristics of single molecules from first principles.[1-3] However, the magnitude of the electrical current obtained from such model calculations are several orders of magnitudes higher than the electrical current measured in experimental verifications of single molecule contacts. The origin of this discrepancy may either be due to the approximations used within the theoretical methods, or the use of idealized geometries for the single molecule contact. . In this talk I will review the latest developments in modelling the electrical properties of single molecules. I will present benchmark calculations for different molecular systems, where the theoretical limit within a certain model chemistry is systematically approached. The applicability of different model chemistries for weak and strongly bonded molecules will be discussed. [1] M. Di Ventra, S.T. Pantelides, N.D. Lang, Phys. Rev. Lett. 84, 979 (2000); [2]J. Taylor, H. Guo, and J. Wang, Phys. Rev. B 63, 121104 (2001); [3]M. Brandbyge, J. L. Mozos, P. Ordejon, J. Taylor, K. Stokbro, Phys. Rev. B. 65, 165401 (2002). (www.atomistix.com)

Nanotech 2004 Conference Technical Program Abstract