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  • Autor
    • Scharfetter, Hermann
    • Fischer, Roland
    • Krassnig, Paul
    • Thonhofer, Martin
    • Theyer, Felix
    • Gösweiner, Christian
  • TitelTris(2-Methoxyphenyl)Bismuthine Polymorphism Characterized by Nuclear Quadrupole Resonance Spectroscopy
  • Datei
  • DOI10.3390/cryst9090446
  • Persistent Identifier
  • Erschienen inCrystals
  • Band9
  • Erscheinungsjahr2019
  • Heft9
  • Seiten446
  • LicenceCC BY
  • ISSN2073-4352
  • ZugriffsrechteCC-BY
  • Download Statistik245
  • Peer ReviewJa
  • AbstractBased on the previous identification of metastable polymorphs in crystalline triphenylbismuth by nuclear quadrupole resonance spectroscopy (NQRS), the potential formation of similar phases was studied in Tris(2-Methoxyphenyl)Bismuthine. To this end, commercial samples with known NQRS properties were molten and re-crystallized at different speeds (shock freezing in different coolants versus slow cooling inside of a heater). In all recrystallization products we have identified a new crystal phase which has not been observed after synthesis from a solution. The new crystallographic structure has been confirmed by X-ray diffraction (XRD). The newly isolated polymorph crystallizes in the monoclinic space group P2(1)/c with only one molecule in the asymmetric unit and consequently only one 5/2-7/2 transition is observed at 88.75 MHz at 310 K. In contrast, the two transitions at 89.38 and 89.29 MHz for the well-known trigonal polymorph originate from two crystallographically distinct molecules of Tris(2-methoxy- Phenyl)Bismuthine in the asymmetric unit. Additional relaxometric NQRS shows distinctly different T 2 relaxation times for the new polymorph when compared to the original samples. Additional phase transitions could not be observed during temperature sweeps between 153K and 323K.