New Applications of the Invariom Database
von Claudia Manuela Wandtke
Datum der mündl. Prüfung:2016-12-12
Betreuer:Prof. Dr. George M. Sheldrick
Gutachter:Prof. George M. Sheldrick
Gutachter:PD Dr. Birger Dittrich
EnglischThree new applications of the Invariom database have been developed and discussed. All applications are in the field of chemical crystallography or molecular modeling. As prerequisite, the invariom database itself was completely renewed and expanded. Due to a more extensive basis set, the new database also allowed homogeneous treatment of structures that contain coordination compounds with 3d-metals. Aspherical scattering factors for complexes were specifically tailored by an invariom-like approach, which allowed identification of the correct metal atom from X-ray diffraction data. In further projects, new properties transferable via invariom classification were introduced. First, fits of atomic point charges to the electrostatic potentials deduced from molecular wave functions built the basis for invariom point charges. Those charges were validated against different theoretically obtained potentials and compared to results from charge-density refinements. Second, the addition of bond-oriented deformation density for modeling of aspherical atomic electron density distributions with Shelxl, transferable from the invariom database, was prepared for future application in form of a pilot study. Overall, new applications of the invariom database were developed, interesting cases were studied by special invariom treatment and a basis for better access to the improved modeling by aspherical scattering factors was provided.
Keywords: deformation density; charge density; atomic charges; invariom; invariom database; small-molecule crystallography; X-ray crystallography