Chemical Bonding in Physical Space
The goal is the complete chemical characterization of the electronic structure of a chemical system on the basis of the first-order (1-RDM) and second-order reduced density matrix (2-RDM) in position and momentum space.
This research includes several tasks/challenges:
- Development of chemical bonding (ChemBond) indicators in position and momentum space based on 1- and 2-RDM.
- Extraction of ChemBond information from experimentally accessible quantities, e.g., the electron density.
- Concrete analysis of ChemBond situations in molecules and solids. Complete characterization of ChemBond situations on the basis of physical space ChemBond indicators.
- Recovering and reformulating known ChemBond concepts from other conceptual frameworks, e.g., the Hilbert space of wavefunctions.
- Refining and extending known, and establishing new ChemBond concepts on the basis of physical space ChemBond indicators.
- Understanding and predicting chemical and physical properties on the basis of the ChemBond model developed.
Currently used concepts for position space analysis:
- The QTAIM (Quantum Theory of Atoms in Molecules) partitioning of position space: based on the electron density.
- Localization of electrons in, and delocalization between basins (localization and delocalization index) of variable type: based on the pair density.
- Localizability of an electron around a certain position (electron localizability indicator, ELI): based on the pair density.
- Interacting Quantum Atoms (IQA) Approach: based on 2-RDM.