Diffusion mechanism of network-forming elements in silicate liquids
Source abstract
Abstract
Abstract Accurate knowledge of the diffusion mechanism of network-forming elements (NFs) in silicate liquids is essential for modeling transport properties such as the shear viscosity. Previous studies focusing on alkali diffusion in silicate liquids/glasses have revealed that alkali ions diffuse via thermal hopping event. However, the diffusion mechanism for NFs remains poorly understood. Herein, molecular dynamics simulations and various analysis methods based on chemical species and bond-breaking events are presented. The analysis results reveal the following diffusion mechanism of NF. Oxygen atoms diffuse similar to a site exchange through the non-bridging oxygen (NBO) state. By contrast, Si diffusion is unlike the exchange regime, and occurs gradually through a bond-exchange event, deforming the network. The dominant mechanism is a rare long flight during Si—O bond breaking, and most bond-breaking events do not contribute, similar to local events. The supporting mechanism is network deformation after a bond-exchange event.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Glass properties and applications · Material Dynamics and Properties · Theoretical and Computational Physics
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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