Joint Research Projects and Cooperations

Kooperations-LogosStefanie Dehnen
DFG Collaborative Research Center SFB 1573 “4f for Future”

Complex materials based on rare earths are applied in many high technologies, such as permanent magnets or screens. Chemistry of molecular and nanoscaled rare earth compounds and their physical properties are now in the focus of the new Collaborative Research Center “4f for Future.” The CRC is coordinated by Karlsruhe Institute of Technology (KIT). The partners are University of Marburg, LMU Munich, and University of Tübingen. As of January 1, 2023, the Collaborative Research Center will be funded by the German Research Foundation (DFG) with more than EUR 10 million for a duration of four years.

Materials based on rare earth metals and their compounds are of crucial importance to our modern high-tech society. Surprisingly, molecular chemistry of these elements is poorly developed. However, recent progress in this area has shown that this is going to change. In the past years, dynamic developments in the chemistry and physics of molecular rare earth compounds have shifted borders and paradigms that existed for decades.

Materials with Unprecedented Properties

“With our joint research initiative “4f for Future”, we want to establish a world-leading center that picks up these new developments and advances them to the extent possible,” says CRC spokesman Professor Peter Roesky from KIT’s Institute for Inorganic Chemistry. The researchers will study synthesis paths and physical properties of new molecular and nanoscaled rare earth compounds in order to develop materials with unprecedented optical and magnetic properties.

Their research is aimed at extending knowledge of the chemistry of molecular and nanoscaled rare earth compounds and at improving the understanding of physical properties for new applications. The CRC will combine the expertise of KIT researchers in the chemistry and physics of molecular rare earth compounds with the know-how of researchers from the universities of Marburg, LMU Munich, and Tübingen.

3D Matter Made to Order – 3DMM2O: Printable Organotetrelchalcogenid Clusters with Non-Linear Optical Properties


Cluster-Based Inks

We reported amorphous molecular materials exhibiting extreme non-linear optical properties. These materials allow to transform infrared light from a CW laser diode into a broad emission, in some cases even white-light generation (WLG). Currently, such compounds are further functionalized in order to increase their solubility in solvents suitable for ink preparation and ink-printing.

Emissive Cluster Glasses for Extrusion Printing

Adamantane-type clusters with two different group 14 element atoms T and CH2 beside E bridges within a quaternary cluster core–[(PhSi)(CH2)3(PhSn)3E3] (E: S, Se, Te)–exhibit low melting points and form glassy materials of high quality. These compounds produce highly homogeneous amorphous solids at moderate temperatures Tg. In first studies, such glasses showed to be excellent WLG materials, which the single-crystalline compounds do not show any non-linear response below the melting point. Such glasses will be tested and optimized for extrusion printing in order to form nanostructures materials with non-linear optical properties.

Synthesis of multi-functional adamantane-clusters

With the idea of continuing our studies on glassy materials based on adamantane-type compounds and the idea to generate new compounds that may have other or additional physical properties, we will continue to expand the library of homogeneous clusters of the type [(RT)4E6] and heterogeneous adamantane-type clusters with the general formula [(RSi)(PhSn)3(CH2)E3]. In this part of the project, we focus on the introduction of new functional groups in position R. We will use these compounds to form materials for extrusion printing, and also for inks.

DFG Research Unit FOR 2824 "Amorphous Molecular Materials with Extreme Non-Linear Optical Properties"

FOR 2824

The DFG Research Unit FOR 2824 focuses on the collaborative elucidation of a new type of whitelight generation (WLG) and whitelight emission, including the synthesis of suitable compounds and their thorough investigation by means of various experimental and theoretical techniques. For this, a straight-forward joint work program was established, the success of which largely depends on a supportive infrastructure, optimal logistics, and functional interaction within and outside the network. While measures for research data and knowledge management, to advance research
careers, and for national and international cooperation and networking are outlined above in this proposal, this section describes how success of FOR 2824 will be underpinned and secured by the overarching coordination project. The funds we apply for in this project shall be used for organizational expenses, such as funding of an administrative staff member, but also for additional expenses that are closely related to the research targets, like flexible funds for additional travel and publication costs, for visiting scientists, student assistants, and workshops, as well as for additional consumables on short-term requirements. The coordination project will also address research-related social issues like gender equality measures, and the communication of scientific results, methods, and values from our specialized research field to people outside the disciplines.

MOSLA - Molecular Storage for Long-Term Archiving

MOSLA develops trans-disciplinary approaches to the solution for one of mankind’s fundamental problems: the long-term storage of information. The development of molecular storage, both for elemental organic cluster elements and DNA molecules, is to be advanced. The scenario of a “digital dark age”, i.e. the loss of all digital information, should thus be prevented. MOSLA’s research regarding DNS as an information storage medium focuses on two core areas MOSLA: Increasing the storage density of DNA, e.g. through better algorithms for data coding and the use of modified nucleotides, as well as information storage in living cells (spores).


Expired cooperation projects

DFG Collaborative Research Center SFB 1083 "Structure and Dynamics of Internal Interfaces"

SFB 1083

In our project in the framework of SFB 1083, we investigate the geometry and the electronic structures of interfaces on a molecular level. We synthesize crystalline multi-layer nano-clusters. These possess an inorganic core MxEy (M = transition metal, E = S, Se, Te). The first shell consists of group 14 dichalcogenides TE2 (T = Ge, Sn). Attached to this shell is a covalently bonded ligand shel. This shell possesses functional organic groups, which themselves can interact with (semi-)metal atoms on surfaces. By varying the components M, E, and T, we investigate the effects on and the nature of the interfaces, which the single components evoke. All of this is also set into relationship with two-dimensionally stacked systems of the same metal(di)chalcogenide composition.

DFG Graduate School GRK 1782 "Functionalization of Semiconductors"

GRK 1782

Our project within GRK 1782 addresses the synthesis of molecular clusters for the functionalization of semiconductor surfaces. A milestone of our work up to date was the synthesis of the non-crystalline compound [(RdelocSn)4S6] (Rdeloc = 4-(CH2=CH)-C6H4). This compound has the ability to generate directed whitelight in a non-linear process when exposed to continuous-wave IR laser radiation. DOI

DFG Priority Programme SPP 1708 "Material Synthesis near Room Temperature"

SPP 1708

In our project in the framework of SPP 1708 we strive for the optimization and development of sustainable low temperature accesses to crystalline chalcogenido metalates using ionothermal syntheses, and for a deeper understanding of the underlying reaction processes. Our target compounds and the corresponding synthesis strategies are: 1) ternary nano-structured, crystalline chalcogenido metalate materials, which are synthesized by unusual precursor combinations and 2) complex and heavy metal-based chalcogenido metalate materials which are obtained by using non-innocent ionic liquids as reaction media. The target compounds were carefully selected based on our previous experience, and the new cooperations developed during the past funding period. Their composition may be generalized using the following formula: (Cat)q[(Mt,c,a,hx)TyEz(R)j][An]p (Cat = Alkali metal, (element-)organic or complex cation; Mt = transition metal; Mc = Pentel metal in a complex cation: Sb, Bi; Ma = triel metal in a complex anion: Ga, In; Mh = heavy metal: Cd, In, Sn, Sb, Hg, Pb, Bi; T = Ge, Sn; E = S, Se, Te; R = organic group; An = (pseudo-)halogenide or complex anion). By varying the composition, specific opto-electronic and thermoelectric properties of the products are addressed, which are analyzed by ourselves or in cooperation within SPP 1708 using various experimental and theoretical methods.

Collaborations with other Groups
FOR2824-Logo Stefanie Dehnen
FOR 2824