The Raman spectra of calcite, Mg-calcite, and dolomite were measured under ambient and high pressure–temperature (P-T) conditions using a hydrothermal diamond anvil cell, for the purpose of developing new pressure …
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Here, we report on the experimental XRD and Raman investigation of calcite which has been saturated and temperature annealed in an H 2 medium at high pressures up to 110 …
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High-pressure phase transformations between the polymorphic forms I, II, III, and IIIb of CaCO3 were investigated by analytical in situ high-pressure high-temperature …
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The recent recognition that marbles in HP (blueschist/eclogite) terranes may record textural evidence for high-pressure conditions raises the possibility that HP textures …
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The room-temperature Raman spectra of aragonite, magnesite and dolomite have been recorded up to 30 GPa and 25 GPa, respectively and no phase changes were observed during …
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Physics of the Earth and Planetary Interiors, 34 (1984) 195-203 195 Elsevier Science Publishers B.V., Amsterdam - Printed in The Netherlands Experimental study of the elasticity of …
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Here, based on high-pressure-temperature experiments, the authors present a reversible temperature-induced transition from aragonite to amorphous CaCO3. ... K. Structural …
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Helium diffusion in carbonates under mantle pressure is crucial for understanding thermal and chemical evolution of mantle. Based on the density functional theory (DFT) and …
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Dolomite calcination in N 2 and CO 2 has been extensively researched [[18], [19], [20]].The general and fairly simplified view is that dolomite decomposes in a single step at a …
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Keywords: Aragonite; Pseudomorph; Greek Aegean Islands; High-pressure metamorphism; Marble; Deformation 1. Introduction Aragonite, a high-pressure polymorph of calcite, is the …
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In this work, we report an experimental observation of a new CaCO 3 calcite-Vb phase, which occurs as the intermediate between aragonite and calcite-V at pressures >3.5 GPa and temperatures >1200 °C, suggesting it …
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The transition temperature of calcite-aragonite decreases with pressure at low pressure from 1.5 to 2.4 GPa but increases with pressure at high pressure from 2.4 to 12 GPa . This is inconsistent with Bridgman (1939), Hess …
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Various experimental works have shown that calcium carbonates exists in five different phases (calcite I, II, III, IV, and V) over ranges of pressure and temperature [2], …
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Dense and strong calcite (CaCO 3) ceramics were prepared by room-temperature cold sintering with the aid of water and high pressure of up to 900 MPa.Under atmospheric …
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5 Center for High Pressure Science and Technology Advanced Research, Beijing 100193, People's Republic of China; 6 Moscow Institute of Physics and Technology, 9 …
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Samples recovered from the high-pressure high-temperature synthesis were then compressed in a DAC and studied by Raman and Fourier transform infrared (FTIR) …
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Calcite, CaCO 3, undergoes several high pressure phase transitions.We report here the crystal structure determination of the CaCO 3-III and CaCO 3-VI high-pressure polymorphs …
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Here, the Z method was employed to calculate the melting points of five high-pressure calcite phases (aragonite, post-aragonite, P2 1 /c-h-CaCO 3, C222 1 –CaCO 3, and …
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For the stability of single carbonate under high-pressure and high-temperature conditions, dolomite CaMg(CO 3) 2, magnesite MgCO 3, and calcite CaCO 3 can survive in the …
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We document the presence of a high pressure phase transition in metastable calcite-III using infrared spectroscopy. The post-calcite-III transition initiates at a pressure of …
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In-situ powder X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectra were measured on the natural crystals of calcite (Ca0.996Mg0.004CO3), dolomite …
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Novel high-pressure calcium carbonates Xi Yao, Congwei Xie, Xiao Dong, Artem R. Oganov, and Qingfeng Zeng ... CaCO3 successively adopts five phases (calcite R-3c, …
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We document the presence of a high pressure phase transition in metastable calcite-III using infrared spectroscopy. The post-calcite-III transition initiates at a pressure of …
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Phase transitions in calcite, a naturally occurring crystalline form of CaCO3, have been investi-gated by three different experimental techniques: (1) in-situ X-ray diffraction (XRD) using …
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The low reaction rate of CaCO3 in the low-pressure calcite stability field may be controlled by two factors: (i) the calcite phase is more stable than the aragonite phase and less …
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The high-pressure response of the cell parameters of calcite, CaCO3, has been investigated by single crystal X-ray diffraction. The unit cell parameters have been refined from 0 to 1.435 GPa, …
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Calcite-III was always found to exist at pressures above 20 kbar at room temperature. It was often observed that calcite-I transformed directly to calcite-III with …
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In situ Raman scattering and electrical conductivity experiments have been performed to investigate the structural phase transitions of calcite during the compressed and decompressed processes in a diamond anvil cell …
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In this study, two separate high pressure-temperature XRD experiments using either NaCl or KCl as the pressure medium have confirmed that CaCO 3-VII is stable up to 2,300 K …
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The high pressure phases of calcite, such as calcite II and calcite III, were first discovered by Bridgman using volumetric measurements in a piston-cylinder [9]. ...
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