High‐temperature raman spectroscopy of SiO₂ and GeO₂ Polymorphs: Anharmonicity and thermodynamic properties at high‐temperatures

Characterization of theTiSiO4structure and its pressure-induced phase transformations: Density functional theory study

“…In addition, these modes can be well correlated with the stretching vibrations of the free-ion ͑SiO 4 ͒ −4 molecule and those of SiO 4 tetrahedra in SiO 2 polymorphs. 53 This fact supports the assumption that the frequency modes of TiSiO 4 , as a first approximation, can be separated between internal and external vibrations. It is interesting to compare the frequencies of zircon TiSiO 4 with other zircon-type silicates.…”

Micro-Raman Spectroscopy of Decorated Pottery of the Diaguita Culture From Iv Region, Chile (9th-15th Century Ad)

“…However, it was possible to identify the characteristic sharp band of quartz at 464 cm -1 . This normal mode attributed to the Si-O stretching vibration, showing some degree of shifting wavenumbers due to variations in the crystallinity of the sample, has been reported by several authors [14][15][16][17] . Figure 2.…”

“…Concerning the red color, Raman spectroscopic studies of the composition of archaeological objects (ceramics and other clay pottery) revealed that hematite, αFe 2 O 3 , or derivatives such as Fe 3 O 4 , FeO and FeO(OH), were commonly used as pigments [15][16][17][18][19][20] . 19-24 In accordance to this fact, the micro-Raman spectrum of sectors that present red coloration, Fig.…”

Nanosecond Gated Raman Spectroscopy for Standoff Detection of Hazardous Materials

“…All the samples were put in a quartz cell which was known to have no major Raman scattering in the range of interest for the experiment. 6 The size of quartz cell was 10 × 10 × 45 mm. The quartz cells were put on a platform located standoff distance away from the telescope system.…”