Filters

20232

More filters

20242
Reset filters

Settings

Author: Liu, Fupin × End date: 2024 × Start date: 2024 × Start date: 2020 × DDC: 500 ×

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Nd─Nd Bond in Ih and D5h Cage Isomers of Nd2@C80 Stabilized by Electrophilic CF3 Addition
    (Weinheim : Wiley-VCH, 2023) Yang, Wei; Velkos, Georgios; Rosenkranz, Marco; Schiemenz, Sandra; Liu, Fupin; Popov, Alexey A.
    Synthesis of molecular compounds with metal–metal bonds between 4f elements is recognized as one of the fascinating milestones in lanthanide metallochemistry. The main focus of such studies is on heavy lanthanides due to the interest in their magnetism, while bonding between light lanthanides remains unexplored. In this work, the Nd─Nd bonding in Nd-dimetallofullerenes as a case study of metal–metal bonding between early lanthanides is demonstrated. Combined experimental and computational study proves that pristine Nd2@C80 has an open shell structure with a single electron occupying the Nd─Nd bonding orbital. Nd2@C80 is stabilized by a one-electron reduction and further by the electrophilic CF3 addition to [Nd2@C80]−. Single-crystal X-ray diffraction reveals the formation of two Nd2@C80(CF3) isomers with D5h-C80 and Ih-C80 carbon cages, both featuring a single-electron Nd─Nd bond with the length of 3.78–3.79 Å. The mutual influence of the exohedral CF3 group and endohedral metal dimer in determining the molecular structure of the adducts is analyzed. Unlike Tb or Dy analogs, which are strong single-molecule magnets with high blocking temperature of magnetization, the slow relaxation of magnetization in Nd2@Ih-C80(CF3) is detectable via out-of-phase magnetic susceptibility only below 3 K and in the presence of magnetic field.
  • Thumbnail Image
    Item
    Directed exciton transport highways in organic semiconductors
    ([London] : Nature Publishing Group UK, 2023) Müller, Kai; Schellhammer, Karl S.; Gräßler, Nico; Debnath, Bipasha; Liu, Fupin; Krupskaya, Yulia; Leo, Karl; Knupfer, Martin; Ortmann, Frank
    Exciton bandwidths and exciton transport are difficult to control by material design. We showcase the intriguing excitonic properties in an organic semiconductor material with specifically tailored functional groups, in which extremely broad exciton bands in the near-infrared-visible part of the electromagnetic spectrum are observed by electron energy loss spectroscopy and theoretically explained by a close contact between tightly packing molecules and by their strong interactions. This is induced by the donor–acceptor type molecular structure and its resulting crystal packing, which induces a remarkable anisotropy that should lead to a strongly directed transport of excitons. The observations and detailed understanding of the results yield blueprints for the design of molecular structures in which similar molecular features might be used to further explore the tunability of excitonic bands and pave a way for organic materials with strongly enhanced transport and built-in control of the propagation direction.