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Vacuum-Level Shift at Al/LiF/Alq₃ Interfaces: A First-Principles Study.

ABSTRACT: Work function changes, or vacuum-level shifts (?_VLS), in Al(001) surfaces by the adsorption of thin layers composed of tris(8-hydroxyquinolinato)aluminum (Alq₃) and/or LiF are theoretically investigated. First-principles calculations reasonably reproduce experimentally obtained ?_VLS values, enabling us to discuss the underlying mechanism. Dipole moment of Alq₃ and interfacial charge rearrangement (Pauli push-back effect) are the main reasons for ?_VLS at Al(001)-Alq₃ and Al(001)-LiF interfaces, respectively. For a stacked Al(001)-LiF-Alq₃ layer configuration, theory suggests a more complicated picture, which takes charge rearrangement between LiF and Alq₃ layers into account, than a simple sum rule of dipole contributions from the two layers.

SUBMITTER: Kondo M

PROVIDER: S-EPMC6705215 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Vacuum-Level Shift at Al/LiF/Alq3 Interfaces: A First-Principles Study.

Kondo Masakazu M Matsushita Takeshi T

ACS omega 20190801 8

Work function changes, or vacuum-level shifts (ΔVLS), in Al(001) surfaces by the adsorption of thin layers composed of tris(8-hydroxyquinolinato)aluminum (Alq3) and/or LiF are theoretically investigated. First-principles calculations reasonably reproduce experimentally obtained ΔVLS values, enabling us to discuss the underlying mechanism. Dipole moment of Alq3 and interfacial charge rearrangement (Pauli push-back effect) are the main reasons for Δ ...[more]

PMID: 31460471

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