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Coexistence of strongly buckled germanene phases on Al(111).

ABSTRACT: We report a study of structural and electronic properties of a germanium layer on Al(111) using scanning tunneling microscopy (STM), low energy electron diffraction and core-level photoelectron spectroscopy. Experimental results show that a germanium layer can be formed at a relatively high substrate temperature showing either (3×3) or (?7×?7)R±19.1° reconstructions. First-principles calculations based on density functional theory suggest an atomic model consisting of a strongly buckled (2×2) germanene layer, which is stable in two different orientations on Al(111). Simulated STM of both orientations fit nicely with experimental STM images and the Ge 3d core-level data decomposed into four components is consistent with the suggested model.

SUBMITTER: Wang W

PROVIDER: S-EPMC5629377 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Coexistence of strongly buckled germanene phases on Al(111).

Wang Weimin W Uhrberg Roger I G RIG

Beilstein journal of nanotechnology 20170918

We report a study of structural and electronic properties of a germanium layer on Al(111) using scanning tunneling microscopy (STM), low energy electron diffraction and core-level photoelectron spectroscopy. Experimental results show that a germanium layer can be formed at a relatively high substrate temperature showing either (3×3) or (√7×√7)R±19.1° reconstructions. First-principles calculations based on density functional theory suggest an atomic model consisting of a strongly buckled (2×2) ge ...[more]

PMID: 29046842

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