Atomic vibrations in iron nanoclusters: Nuclear resonant inelastic x-ray scattering and molecular dynamics simulations

被引：23

作者：

Roldan Cuenya, B. ^{[1
]}

Naitabdi, A. ^{[1
]}

Croy, J. ^{[1
]}

Sturhahn, W. ^{[2
]}

Zhao, J. Y. ^{[2
]}

Alp, E. E. ^{[2
]}

Meyer, R. ^{[3
]}

Sudfeld, D. ^{[3
]}

Schuster, E. ^{[3
]}

Keune, W. ^{[1
,3
]}

机构：

[1] Univ Cent Florida, Dept Phys, Orlando, FL 32816 USA

[2] Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA

[3] Univ Duisburg Essen, Fachbereich Phys, D-47048 Duisburg, Germany

来源：

PHYSICAL REVIEW B | 2007年 / 76卷 / 19期

关键词：

D O I：

10.1103/PhysRevB.76.195422

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The lattice vibrational dynamics of supported, self-assembled, isolated Fe-57 nanoclusters was studied by nuclear resonant inelastic x-ray scattering and molecular dynamics calculations. The morphological and structural properties and the chemical state of the experimental nanoclusters were investigated by atomic force microscopy, high resolution transmission electron microscopy, and x-ray photoelectron spectroscopy. The measured and calculated vibrational densities of states (VDOSs) reveal an enhancement of the low- and high-energy phonon modes and provide experimental and theoretical proof of non-Debye-like behavior in the low-energy region of the VDOS. Experimentally, this effect was found to depend on the nature of the surface shell (oxide or carbide) of the core/shell nanoclusters. According to the calculations for supported isolated pure Fe nanoclusters, the non-Debye-like behavior appears not only in the surface shell but also in the bcc-Fe core of the nanocluster due to the hybridization of surface and bulk modes.

引用

页数：5

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