Heike Herper is a researcher in the Division of Materials Theory at Uppsala University, Sweden. Her research focuses on the investigation of magnetic materials reaching from bulk to molecules deposited on metals aiming to identify new candidates for applications, in particular to find non-hazardous replacement materials for existing permanent magnets.Barbara Brena is a researcher in the Division of Materials Theory at Uppsala University, Sweden. Her research focuses on electronic structure calculations, in particular she is interested in modeling soft x-ray spectroscopies of organic molecular materials, which are hot candidates for novel and environmental friendly technologies.Carla Puglia is an Associate Professor in the division of Molecular and Condensed Matter Physics at Uppsala University, Sweden. Her research focus is on Many-body effects and excitonic features in materials.Heiko Wende is a Professor and Head of the Magnetic Nanostructures group at theUniversity of Duisburg-Essen. His research interests are in the area of Magnetic molecules; Magnetic Nanoparticles; Magnetic thin films and heterostructures.Olle Eriksson is a Professor in the Division of Materials Theory at Uppsala University, Sweden. His research interests are in first principles calculations of bulk and surfaces, including magnetism and chemical bonding.Biplab Sanyal is currently and Associate Professor in the Division of Materials Theory at Uppsala University, Sweden. His research interests are in the area of material structures. To his credit he has over 200 publications and 70 invited talks. He is a member of IEEE and the American Physical Society.

• 1. Introduction.- 2. Experimental techniques.- 3. Theoretical methods.- 4. Electronic structure of isolated molecules.- 5. Electron correlation and spin transition.- 6. Interaction with substrates.- 7. Influence of ligands.- 8. Applications.