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From Crystalline to Amorphous Germania Bilayer Films at the Atomic Scale: Preparation and Characterization.

ABSTRACT: A new two-dimensional (2D) germanium dioxide film has been prepared. The film consists of interconnected germania tetrahedral units forming a bilayer structure, weakly coupled to the supporting Pt(111) metal-substrate. Density functional theory calculations predict a stable structure of 558-membered rings for germania films, while for silica films 6-membered rings are preferred. By varying the preparation conditions the degree of order in the germania films is tuned. Crystalline, intermediate ordered and purely amorphous film structures are resolved by analysing scanning tunnelling microscopy images.

SUBMITTER: Lewandowski AL

PROVIDER: S-EPMC6771709 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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From Crystalline to Amorphous Germania Bilayer Films at the Atomic Scale: Preparation and Characterization.

Lewandowski Adrián L AL Tosoni Sergio S Gura Leonard L Schlexer Philomena P Marschalik Patrik P Schneider Wolf-Dieter WD Heyde Markus M Pacchioni Gianfranco G Freund Hans-Joachim HJ

Angewandte Chemie (International ed. in English) 20190701 32

A new two-dimensional (2D) germanium dioxide film has been prepared. The film consists of interconnected germania tetrahedral units forming a bilayer structure, weakly coupled to the supporting Pt(111) metal-substrate. Density functional theory calculations predict a stable structure of 558-membered rings for germania films, while for silica films 6-membered rings are preferred. By varying the preparation conditions the degree of order in the germania films is tuned. Crystalline, intermediate or ...[more]

PMID: 31050096

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