Thermodynamics data of Alkali Feldspars from FPMD simulations

Description

We computed the thermodynamic properties (pressure, temperature, internal energy, heat capacity) on the two alkali feldspars end-members using ab initio molecular dynamics simulation in the 2000-20000 K temperature range and in the 0.5-6 g/cm3 density range. Simulations are performed using the Vienna Ab Initio Simulation Package (VASP) (Kresse and Furthmuller, 1996) in the canonical (NVT) ensemble with a timestep of 0.5-2 fs for 5-20 ps depending on the temperature and density. We model the feldspar end-members in a cubic cell containing 208 atoms (16 formula units) and 1024 or 1152 electrons for the Na- and K-feldspars respectively. For simulations below 1 g/cm3 we used softer pseudopotentials. For Na-end-member above 3 g/cm3 we used harder pseudo potentials. Additional details can be found in the manuscript.   There is one dataset for each different composition and pseudopotentials used: kobsch-ds01.txt    -->    NaAlSi3O8 kobsch-ds02.txt    -->    NaAlSi3O8 and softer pseudopotentials than in 01 kobsch-ds03.txt    -->    NaAlSi3O8 and harder pseudopotentials than in 01 kobsch-ds04.txt    -->    KAlSi3O8 kobsch-ds05.txt    -->    KAlSi3O8 and softer pseudopotentials than in 04   Each file present the time averages of the pressure (\(\overline{P}\)), temperature (\(\overline{T}\)) and internal energy (\(\overline{E}\)) in all the simulations. The standard deviation of the data to the mean is indicated by \(\sigma_X\), where X is P, T or E. The statistical error to the mean (\(\sigma_{\overline{X}}\)) is computed using the blocking method as described by Flyvbjerg and Petersen (1989). The sign '>' is indicated before the value of the statistical error when no convergence  was reached during the estimation of this error. The heat capacity Cv is computed using fluctuations on both potential and kinetic energies (Allen and Tildesley, 1989) and its statistical error \(\sigma_{Cv_m}\) is computed using the bootstrap method.

Resources

Name Format Description Link
0 http://data.europa.eu/88u/dataset/oai-zenodo-org-3609986
0 http://data.europa.eu/88u/dataset/oai-zenodo-org-3609986
0 http://data.europa.eu/88u/dataset/oai-zenodo-org-3609986
0 http://data.europa.eu/88u/dataset/oai-zenodo-org-3609986
0 http://data.europa.eu/88u/dataset/oai-zenodo-org-3609986
0 http://data.europa.eu/88u/dataset/oai-zenodo-org-3609986

Tags

  • ab-initio-molecular-dynamics
  • thermodynamics
  • alkali-feldspars

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