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Quantitative determination of a model organic/insulator/metal interface structure.

ABSTRACT: By combining X-ray photoelectron spectroscopy, X-ray standing waves and scanning tunneling microscopy, we investigate the geometric and electronic structure of a prototypical organic/insulator/metal interface, namely cobalt porphine on monolayer hexagonal boron nitride (h-BN) on Cu(111). Specifically, we determine the adsorption height of the organic molecule and show that the original planar molecular conformation is preserved in contrast to the adsorption on Cu(111). In addition, we highlight the electronic decoupling provided by the h-BN spacer layer and find that the h-BN-metal separation is not significantly modified by the molecular adsorption. Finally, we find indication of a temperature dependence of the adsorption height, which might be a signature of strongly-anisotropic thermal vibrations of the weakly bonded molecules.

SUBMITTER: Schwarz M

PROVIDER: S-EPMC6289171 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Quantitative determination of a model organic/insulator/metal interface structure.

Schwarz Martin M Duncan David A DA Garnica Manuela M Ducke Jacob J Deimel Peter S PS Thakur Pardeep K PK Lee Tien-Lin TL Allegretti Francesco F Auwärter Willi W

Nanoscale 20181101 46

By combining X-ray photoelectron spectroscopy, X-ray standing waves and scanning tunneling microscopy, we investigate the geometric and electronic structure of a prototypical organic/insulator/metal interface, namely cobalt porphine on monolayer hexagonal boron nitride (h-BN) on Cu(111). Specifically, we determine the adsorption height of the organic molecule and show that the original planar molecular conformation is preserved in contrast to the adsorption on Cu(111). In addition, we highlight ...[more]

PMID: 30444513

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