Vibrational properties of a two-dimensional silica kagome lattice

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.