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Direct measurement of Ni incorporation into Fe₃O₄(001).

ABSTRACT: The normal incidence X-ray standing wave (NIXSW) technique has been used to follow the evolution of the adsorption geometry of Ni adatoms on the Fe3O4(001)-(?2 × ?2)R45° surface as a function of temperature. Two primary surface region sites are identified: a bulk-continuation tetrahedral site and a sub-surface octahedral site, the latter site being preferred at higher annealing temperatures. The ease of incorporation is linked to the presence of subsurface cation vacancies in the (?2 × ?2)R45° reconstruction and is consistent with the preference for octahedral coordination observed in the spinel compound NiFe2O4.

SUBMITTER: Ryan PTP

PROVIDER: S-EPMC6011209 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Direct measurement of Ni incorporation into Fe3O4(001).

Ryan P T P PTP Jakub Z Z Balajka J J Hulva J J Meier M M Küchle J T JT Blowey P J PJ Thakur P Kumar PK Franchini C C Payne D J DJ Woodruff D P DP Rochford L A LA Allegretti F F Lee T-L TL Parkinson G S GS Duncan D A DA

Physical chemistry chemical physics : PCCP 20180601 24

The normal incidence X-ray standing wave (NIXSW) technique has been used to follow the evolution of the adsorption geometry of Ni adatoms on the Fe3O4(001)-(√2 × √2)R45° surface as a function of temperature. Two primary surface region sites are identified: a bulk-continuation tetrahedral site and a sub-surface octahedral site, the latter site being preferred at higher annealing temperatures. The ease of incorporation is linked to the presence of subsurface cation vacancies in the (√2 × √2)R45° r ...[more]

PMID: 29882949

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