Thermoelastic properties of ringwoodite (Fex,Mg1 x)2SiO4: Its relationship to the 520 km seismic discontinuity
نویسندگان
چکیده
We combine density functional theory (DFT) within the local density approximation (LDA), the quasiharmonic approximation (QHA), and a model vibrational density of states (VDoS) to calculate elastic moduli and sound velocities of g-ðFex,Mg1 xÞ2SiO4 (ringwoodite), the most abundant mineral of the lower Earth’s transition zone (TZ). Comparison with experimental values at room-temperature principles findings. Then, we investigate the contrasts associated with the b-gðFex,Mg1 xÞ2SiO4 transformation at pressures and temperatures relevant to the TZ. This information offers clearly defined reference values to advance the understanding of the nature of the 520 km seismic discontinuity. & 2012 Elsevier B.V. All rights reserved.
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