Clustering feature of metal atoms in pentacene molecular solids: first-principles study

Metal-atom contamination often induces the degradation of organic molecular devices. In this work, we studied clustering feature of Au and Al impurity metal atoms in pentacene solids by the first-principles calculations. We found that Au atoms prefer to produce clusters in a molecule-edge space due to the strong bonding among Au atoms, and such clusters can increase their sizes by producing molecule vacancies. On the other hand, Al atom prefers to locate separately around the center of pentacene molecules due to the strong bonding between Al atom and surrounding molecules, which produces the scattering distribution of Al atoms in pentacene solids.

Molecular Dynamics Simulation of Crack Initiation of Aluminum under Tensile Deformation

Molecular dynamics simulation was used to simulate the tension process of purity and containing impurity metal aluminum. Elastic constants of purity and containing impurity metal aluminum were calculated, and the effects of impurity on the elastic constants were also studied. The results show that O-Al bond and Al-Al bond near oxygen atoms could be the sites of crack nucleation or growth under tensile load, the method can be extended to research mechanical properties of other metals and alloys structures.