Motivated by the recent synthesis of two-dimensional ##IMG## [http://ej.iop.org/images/2053-1583/7/2/025029/tdmab6d79ieqn001.gif] -Fe 2 O 3 (Balan et al 2018 Nat. Nanotechnol . 13 602), we analyze the structural, vibrational, electronic and magnetic properties of single- and few-layer ##IMG## [http://ej.iop.org/images/2053-1583/7/2/025029/tdmab6d79ieqn002.gif] -Fe 2 O 3 compared to bulk, by ab initio and Monte-Carlo simulations. We reveal how monolayer ##IMG## [http://ej.iop.org/images/2053-1583/7/2/025029/tdmab6d79ieqn003.gif] -Fe 2 O 3 (hematene) can be distinguished from the few-layer structures, and how they all differ from bulk through observable Raman spectra. The optical spectra exhibit gradual shift of the prominent peak to higher energy, as well as additional features at lower energy when ##IMG##

中文翻译：

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赤铁矿的最薄极限

受二维## IMG ##最近合成的启发[http://ej.iop.org/images/2053-1583/7/2/025029/tdmab6d79ieqn001.gif] -Fe 2 O 3（Balan等2018 Nat。Nanotechnol。13602），我们分析了单层和多层## IMG ## [http://ej.iop.org/images/2053-1583/7的结构，振动，电子和磁性/2/025029/tdmab6d79ieqn002.gif]-从头算和蒙特卡洛模拟，Fe 2 O 3与体相比较。我们揭示了如何区分单层## IMG ## [http://ej.iop.org/images/2053-1583/7/2/025029/tdmab6d79ieqn003.gif] -Fe 2 O 3（麻黄）层结构，以及通过可观察的拉曼光谱，它们与体积的区别。当## IMG ##时，光谱显示出突出的峰逐渐转移到更高的能量，并且在更低的能量下表现出附加特征