Structure and elasticity of CaCO suggests carbonate contribution to the seismic anomalies of Earth's mantle.

Knowledge of carbonate compounds under high pressure inside Earth is key to understanding the internal structure of the Earth, the deep carbon cycle and major geological events. Here we use first-principles simulations to calculate the structure and elasticity of CaCO-minerals with different symmetries under high pressure. Our calculations show that CaCO-minerals represent a group of low-density low-seismic-wave velocity mantle minerals.

Raman spectroscopic quantitative study of NaCl-CaCl2-H2O system at high temperatures and pressures.

Raman spectra features of the ternary system NaCl-CaCl2-H2O under high temperatures and high pressures were systematically studied in the present work by using hydrothermal diamond anvil cell (HDAC) and Raman shifts of quartz to determine pressures, and it has been obtained for the quantitative relationship between Raman shifts of the O-H stretching band of water, mass fractions of solutes and pressures was obtained. The mass fractions of salts, where salinity of NaCl equal to that of CaCl2, are 4.0 mass %, 8.