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Hans Jørgen Aagaard Jensen


Phone: +45 6550 2512

My research evolves around the development of new and better theories for simulating the properties of molecules. The properties are determined by the molecule's electron configuration, i.e. the distribution of the electrons in the molecule, which follows the laws of quantum mechanics. The new methods are implemented in computer programs, which are used by researchers all over the world.

I am one of the main authors of two major quantum chemical program systems, Dalton (Http:// and Dirac (, which we continually develop in close cooperation with researchers in other countries. Dalton, like most of the quantum chemical programs, is primarily for calculations on molecules with atoms from the top half of the periodic system. For molecules with heavier atoms (roughly from the bottom half of the periodic system) one has to take into account relativistic effects and incorporate the speed of light to get good results of the simulations. This can be done based on the Dirac equation instead of the well-known Schrödinger equation in quantum mechanics, and that is exactly what we have achieved with the program Dirac, which is a unique tool for calculations with heavy atoms. Dirac was therefore selected as one of 13 computer programs for research to be used to optimize Summit, the world's currently largest supercomputer at Oak Ridge National Laboratory, USA (see At the moment, we are primarily developing new methods for simulating the chemistry and spectroscopy of metal complexes and actinides.