Multireference ab-initio studies of magnetic properties of TbPc2- type single-molecule magnets
Kyungwha Park
Department of Physics, Virginia Tech, Blacksburg, VA 24061 USA
Recent advances have allowed the experimental realizations of quantum bits and quantum gates by using molecular magnets as active elements, as well as the experimental implementation of quantum algorithms within them. In particular, lanthanide-based single-molecule magnets are promising for such applications because of strong spin-orbit interaction, molecular geometry compatible to devices, and tunability of coupling between electron and nuclear spins via electric field. So far, there is a lack of systematic ab-initio studies on magnetic properties of such single-molecule magnets. Here we investigate electronic structure and magnetic properties of TbPc2 and TbPcNc single-molecule magnets as a function of oxidation state, ligand type and distortion of molecular geometry, using first-principles relativistic multireference methods including spin-orbit interaction. By applying effective pseudospin Hamiltonian to the lowest multiplet, we compute crystal-field parameters and examine the dependence of several important energy scales on these chemical factors. Furthermore, we discuss coupling of electron spin to nuclear spin within the single-molecule magnets using multireference quantum chemistry methods. Our calculated results are compared to experimental data.
* Acknowledgment: This work was done in collaboration with Ryan Pederson, Aleksander Wysocki, and Nicholas Mayhall from Virginia Tech. This work was funded by the Department of Energy Basic Energy Sciences grant No DE SC0018326. Computational support was provided by Virginia Tech ARC.