Molecular Dynamics Calculations of the Thermal Conductivity of Silica Based Crystals
نویسنده
چکیده
The thermal conductivities of quartz and the siliceous zeolites sodalite, faujasite and zeolite-A have been calculated using molecular dynamics simulations. The predicted thermal conductivities range over one order of magnitude at room temperature, and the quartz values are in reasonable agreement with the available experimental data. Evidence of phonon scattering is found by considering the lattice statics and dynamics. The lattice pores in zeolites are found to distort the SiO4 tetrahedra, and decrease the thermal conductivity. The integration of the heat current autocorrelation function in the calculation of the thermal conductivity is done in frequency space, allowing the contributions of different vibrational bands to be identified.
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