MedeA® Application Notes for Glass & Ceramics

In addition to the lattice parameters, the rutile structure has an additional degree of freedom, namely the position of the oxygen atom. This case study shows the simultaneous calculation of all these structural degrees of freedom.

Structure and Bond Lengths in Titanium Dioxide (TiO₂)

The introduction of vacancies in a crystalline solid causes a local rearrangement of atoms around
the defect. The purpose of this case study is the prediction of such changes in α-quartz.

Structure around Oxygen Vacancy in α-Quartz

Despite the enormous progress in experimental surface science, notably with spectroscopic methods exploiting synchrotron radiation and scanning tunneling microscopy, computations remain one of the most useful sources for accurate data on surface structures. In fact, quite often it is the combination of experimental and computed results, which gives the most reliable data of surface structures. As an example, let us apply MEDEA to the Si(001) surface. This surface is the typical substrate in the manufacturing of semiconducting devices.

Surface Reconstruction of Si(001)