Order-disorder phase transition on the (100) surface of magnetite

被引：24

作者：

Bartelt, Norman C. ^{[1
]}

Nie, Shu ^{[1
]}

Starodub, Elena ^{[1
]}

Bernal-Villamil, Ivan ^{[2
]}

Gallego, Silvia ^{[2
]}

Vergara, Lucia ^{[3
]}

McCarty, Kevin F. ^{[1
]}

de la Figuera, Juan ^{[3
]}

机构：

[1] Sandia Natl Labs, Livermore, CA 94550 USA

[2] CSIC, Inst Ciencia Mat Madrid, E-28049 Madrid, Spain

[3] CSIC, Inst Quim Fis Rocasolano, E-28006 Madrid, Spain

来源：

PHYSICAL REVIEW B | 2013年 / 88卷 / 23期

关键词：

SCANNING-TUNNELING-MICROSCOPY; ENERGY-ELECTRON-DIFFRACTION; VERWEY TRANSITION; FE3O4(001); RECONSTRUCTION; FE3O4(100); GAS;

D O I：

10.1103/PhysRevB.88.235436

中图分类号：

T [工业技术];

学科分类号：

120111 [工业工程];

摘要：

Using low-energy electron diffraction, we show that the room-temperature (root 2 x root 2) R45 degrees reconstruction of Fe3O4(100) reversibly disorders at similar to 450 degrees C. Short-range order persists above the transition, suggesting that the transition is second order and Ising-like. We interpret the transition in terms of a model in which subsurface Fe3+ is replaced by Fe2+ as the temperature is raised. This model reproduces the structure of antiphase boundaries previously observed with scanning tunneling microscopy, as well as the continuous nature of the transition. To account for the observed transition temperature, the energy cost of each charge rearrangement is 82 meV.

引用

页数：5

共 37 条

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