抄録
Defects in crystals such as surfaces, interfaces, and grain boundaries significantly affect mechanical responses of materials under deformation in microscopic scale. While locally-distributed energy and stress obtained by ab-initio method are considered to be useful tools for capturing the local effects of defects inside crystals, topological analysis of electron density proposed by Bader is another way to approach such local effects. Estimating the changes of electron density or its curvatures on some specific points such as bond midpoints, we can obtain the characteristics of the local electronic structure as well as by the partial density of states or the bond order. In this study, we have performed the topological analysis and the PDOS analysis on shear deformation of diamond crystals, carbon, Si, and Ge. Using the results, we conclude that the stress responses depend on the balance between the bonding strength and the angular dependence of sp3 configuration.
