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Probing of 2 dimensional confinement-induced structural transitions in amorphous oxide thin film.

ABSTRACT: Whereas the atomic structure of surface of crystals is known to be distinct from that of bulk, experimental evidence for thickness-induced structural transitions in amorphous oxides is lacking. We report the NMR result for amorphous alumina with varying thickness from bulk up to 5 nm, revealing the nature of structural transitions near amorphous oxide surfaces/interfaces. The coordination environments in the confined amorphous alumina thin film are distinct from those of bulk, highlighted by a decrease in the fractions of high-energy clusters (and thus the degree of disorder) with thickness. The result implies that a wide range of variations in amorphous structures may be identified by controlling its dimensionality.

SUBMITTER: Lee SK

PROVIDER: S-EPMC3935193 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

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Probing of 2 dimensional confinement-induced structural transitions in amorphous oxide thin film.

Lee Sung Keun SK Ahn Chi Won CW

Scientific reports 20140226

Whereas the atomic structure of surface of crystals is known to be distinct from that of bulk, experimental evidence for thickness-induced structural transitions in amorphous oxides is lacking. We report the NMR result for amorphous alumina with varying thickness from bulk up to 5 nm, revealing the nature of structural transitions near amorphous oxide surfaces/interfaces. The coordination environments in the confined amorphous alumina thin film are distinct from those of bulk, highlighted by a d ...[more]

PMID: 24569515

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