Ab Initio Molecular Dynamic Simulation on the Elasticity of Mg3Al2Si3O12 Pyrope
نویسندگان
چکیده
We calculated thermo-elastic properties of pyrope (Mg3Al2Si3O12) at mantle pressures and temperatures using Ab initio molecular dynamic simulation. A third-order Birch-Murnaghan equation at a reference temperature of 2 000 K fits the calculations with bulk modulus, K0=159.5 GPa, K0’=4.3, V0=785.89 Å, Grüneisen parameter, γ0=1.15, q=0.80, Anderson Grüneisen parameter δT=3.76 and thermal expansion, α0=2.93×10 K. Referenced to room temperature, where V0=750.80 Å, γ0 and α0 become 1.11 and 2.47×10 K. The elastic properties of pyrope are found to be nearly isotropic at transition zone conditions.
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