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Dipole formation at metal/PTCDA interfaces: Role of the Charge Neutrality Level

H. Vazquez·R. Oszwaldowski·P. Pou·J. Ortega·R. Perez·F. Flores·A. Kahn
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Abstract

The formation of a metal/PTCDA (3, 4, 9, 10-perylenetetracarboxylic dianhydride) interface barrier is analyzed using weak-chemisorption theory. The electronic structure of the uncoupled PTCDA molecule and of the metal surface is calculated. Then, the induced density of interface states is obtained as a function of these two electronic structures and the interaction between both systems. This induced density of states is found to be large enough (even if the metal/PTCDA interaction is weak) for the definition of a Charge Neutrality Level for PTCDA, located 2.45 eV above the highest occupied molecular orbital. We conclude that the metal/PTCDA interface molecular level alignment is due to the electrostatic dipole created by the charge transfer between the two solids.

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H. Vazquez, R. Oszwaldowski, P. Pou, J. Ortega, R. Perez, F. Flores, A. Kahn. 2004-05-21. Dipole formation at metal/PTCDA interfaces: Role of the Charge Neutrality Level. https://doi.org/10.1209/epl%2Fi2003-10131-2

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