The Cheng group develops novel electronic-structure methods and applies them in chemical and spectroscopic studies. The ultimate goal in the area of electronic-structure theory is perhaps to have a set of quantum-chemical methods and computer programs that are generally applicable to the entire periodic table and to both ground and excited electronic states. Our present work focuses on the treatment of relativistic effects on molecular properties.
An accurate and efficient treatment of relativistic effects remains a challenging task for quantum-chemical calculations, while promising progress has occurred in the past a few decades leading to a hierarchy of relativistic quantum-mechanical approaches that systematically relates the non-relativistic world (Schrodinger equation) to the relativistic world (Dirac equation).
Our research group works on algorithms and computer programs for treating relativistic effects in computations of molecular energies and properties (electrical properties, magnetic properties, as well as spin-orbit-dependent parameters). Newly developed methods are applied to a variety of chemical and spectroscopic problems involving heavy elements (coinage metals, lanthanides, actinides, etc).