Bond valences mismatch pathways

Bond Valence Mismatch Pathways Versus Bond Valence Site Energy Pathways. 132... 

For the bond valence mismatch pathways, regions of low bond valence sum mismatch (and hence implicitly low site energy) for an ion M" are modeled as regions in the structure, where the bond valence sum F(M)... 

Adams S, Prasada Rao R (2009) Transport pathways for mobile ions in disordered solids from the analysis of energy-scaled bond-valence mismatch landscapes. Phys Chem Chem Phys 11 3210-3216... 

While it has to be acknowledged that the calculation of these BVSE landscapes requires a little bit more computational effort than the calculation of bond valence mismatch landscapes, the fact that the same parameters used to calculate these static pathway models are also suitable as a highly transferable force field for molecular dynamics simulations of a wide range of oxides appears to be a major... 

Procrystal electron density threshold for a migration pathway Bond valence site energy threshold for a migration pathway Absolute bond valence sum mismatch Bond valence sit energy of ion M Density functional theory... 

As mentioned above, Garrett et al. [1] first demonstrated the equivalence of the bond valence sum mismatch pathways in a-Agl with pathways determined experimentally from an anharmonic atomic displacement refinement of neutron diffraction data as a justification for predicting transport pathways for their then new fast Ag" ion conductor Agig I12P 2O7 using the same approach. In our earliest work on pathway models for similar Ag" ion conducting oxyhalide systems [3, 18], we used a parameter set by Radaev et al. [19],... 

A more physical description of the repulsion effects is obviously achieved when such hard cutoff radii are replaced by a Coulomb repulsion term so that with decreasing cation-cation distance pathway regions close to immobile cations become gradually less favorable for the mobile cation. On the other hand, this approach requires a scaling between a bond valence sum mismatch description of attraction terms and an energy-scaled Coulomb repulsion. Despite these shortcomings, ion transport in a variety of crystalline Ag" ion conducting systems such as... 

---