The role played by the molecular geometry on the electronic transport through nanometric organic films. Issue 44 (30th October 2019)

• Record Type: Journal Article
• Authors: Lima, Matheus P.; Miwa, R. H.; Fazzio, A.
• Is Part Of: Physical chemistry chemical physics. Volume 21:Issue 44(2019)
• Page Start: 24584
• Page End: 24591
• Publication Date: 2019-10-30
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c9cp04304g
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : The electronic transport properties in molecular heterojunctions are intimately connected with the molecular conformation between the electrodes, and the electronic structure of the molecule/electrode interface. Abstract : The electronic transport properties in molecular heterojunctions are intimately connected with the molecular conformation between the electrodes, and the electronic structure of the molecule/electrode interface. In this work, we perform an ab initio density-functional-theory investigation of the structural and transport properties through self-assembled CuPc molecules sandwiched between gold contacts with (111) surfaces. We demonstrated (i) a tunneling regime ruled by the π orbitals of the aromatic rings of CuPc molecules; and (ii) a high variation (up to two orders of magnitude) of the current density with the orientation of the CuPc molecules relative to the gold surface. The source of this variation is the geometrical dependence of the energy of the highest-occupied-molecular-orbital with respect to the chemical potential of the metal and the generation of intra-molecular transport channels for a configuration with CuPc molecules tilted with respect to the gold surface.