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Vibrational Properties of a Two-Dimensional Silica Kagome Lattice.

ABSTRACT: Kagome lattices are structures possessing fascinating magnetic and vibrational properties, but in spite of a large body of theoretical work, experimental realizations and investigations of their dynamics are scarce. Using a combination of Raman spectroscopy and density functional theory calculations, we study the vibrational properties of two-dimensional silica (2D-SiO₂), which has a kagome lattice structure. We identify the signatures of crystalline and amorphous 2D-SiO₂ structures in Raman spectra and show that, at finite temperatures, the stability of 2D-SiO₂ lattice is strongly influenced by phonon-phonon interaction. Our results not only provide insights into the vibrational properties of 2D-SiO₂ and kagome lattices in general but also suggest a quick nondestructive method to detect 2D-SiO₂.

SUBMITTER: Bjorkman T

PROVIDER: S-EPMC5198257 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Vibrational Properties of a Two-Dimensional Silica Kagome Lattice.

Björkman Torbjörn T Skakalova Viera V Kurasch Simon S Kaiser Ute U Meyer Jannik C JC Smet Jurgen H JH Krasheninnikov Arkady V AV

ACS nano 20161114 12

Kagome lattices are structures possessing fascinating magnetic and vibrational properties, but in spite of a large body of theoretical work, experimental realizations and investigations of their dynamics are scarce. Using a combination of Raman spectroscopy and density functional theory calculations, we study the vibrational properties of two-dimensional silica (2D-SiO<sub>2</sub>), which has a kagome lattice structure. We identify the signatures of crystalline and amorphous 2D-SiO<sub>2</sub> s ...[more]

PMID: 28024359

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