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Dysprosium(III)-containing single-molecule magnets (SMMs) show blocking of the molecular magnetization and hysteresis effects in one molecule. They belong to the class of the best performing SMMs at present. Here, we present first results of 161Dy-Nuclear Resonance Vibrational Spectroscopy (NRVS) experiments on the dysprosium(III) complex [Dy(H2dapp)(NO3)2](NO3) with H2dapp being 2,6-bis((E)-1-(2-(pyridine-2-yl)-hydrazineylidene)ethyl)pyridine. For the 161Dy-NRVS experiments a compact novel He flow cryostat was used at the Advanced Photon Source, Argonne National Laboratories, which enables low temperature NRVS experiments in helium vapour circumventing the often-observed difference between sensor read and "real" sample temperature in mostly used LHe and/or closed cycle cryostats with the NRVS sample being in vacuum. To explore the vibrational modes of the molecule simulations based on first density functional theory (DFT) calculations are presented. [ABSTRACT FROM AUTHOR]

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Synchrotron‐based nuclear resonance vibrational spectroscopy (NRVS) using the Mössbauer isotope 161Dy has been employed for the first time to study the vibrational properties of a single‐molecule magnet (SMM) incorporating DyIII, namely [Dy(Cy3PO)2(H2O)5]Br3⋅2 (Cy3PO)⋅2 H2O ⋅2 EtOH. The experimental partial phonon density of states (pDOS), which includes all vibrational modes involving a displacement of the DyIII ion, was reproduced by means of simulations using density functional theory (DFT), enabling the assignment of all intramolecular vibrational modes. This study proves that 161Dy NRVS is a powerful experimental tool with significant potential to help to clarify the role of phonons in SMMs. [ABSTRACT FROM AUTHOR]

Time‐domain synchrotron Mössbauer spectroscopy (SMS) based on the Mössbauer effect of 161Dy has been used to investigate the magnetic properties of a DyIII‐based single‐molecule magnet (SMM). The magnetic hyperfine field of [Dy(Cy3PO)2(H2O)5]Br3⋅2 (Cy3PO)⋅2 H2O⋅2 EtOH is with B0=582.3(5) T significantly larger than that of the free‐ion DyIII with a 6H15/2 ground state. This difference is attributed to the influence of the coordinating ligands on the Fermi contact interaction between the s and 4f electrons of the DyIII ion. This study demonstrates that 161Dy SMS is an effective local probe of the influence of the coordinating ligands on the magnetic structure of Dy‐containing compounds. A new point of view: The magnetic hyperfine field at the 161Dy nucleus in Dy‐containing compounds can be determined by 161Dy time‐domain synchrotron Mössbauer spectroscopy. This quantity is influenced by the polarization of the s electrons at the 161Dy nucleus via metal–ligand interactions. The effect of different ligands in Dy‐containing single‐molecule magnets can now directly be explored from the viewpoint of the lanthanide ion. [ABSTRACT FROM AUTHOR]

Innentitelbild: Untersuchung von Schwingungen in Bezug auf Spin-Phonon-Kopplung in Einzelmolekülmagneten mittels nuklearer inelastischer Streuung am 161Dy-Kern (Angew. Keywords: Dysprosium; Einzelmolekülmagnete; Kernresonanz; Nukleare inelastische Streuung; Phononen; Schwingungsspektroskopie DE Dysprosium Einzelmolekülmagnete Kernresonanz Nukleare inelastische Streuung Phononen Schwingungsspektroskopie 8810 8810 1 05/27/20 20200602 NES 200602 B Hämatit-basierte Mesokristalle b aus hochorientierten Nanopartikelbausteinen zeigen eine überlegene Aktivität in der photoelektrochemischen Wasserspaltung unter Einstrahlung von Sonnenlicht. Wie T. Tachikawa et al. in ihrem Forschungsartikel auf S. 9132 zeigen, sorgen die reichhaltigen Sauerstoffvakanzen an den Grenzflächen für eine außerordentlich hohe Ladungsträgerdichte sowie eng benachbarte Depletionsschichten (<1 nm) innerhalb des mesoporösen Films. [Extracted from the article]

161Dy time-domain synchrotron Mössbauer spectroscopy (SMS), just recently presented as a novel tool to investigate Dy(III)-based single-molecule magnets (SMMs), has now been applied on two polynuclear Dy6-based wheel compounds possessing special features of single-molecule toroics (SMTs). The magnitude of the magnetic hyperfine field revealed for the Dy6 ring system [Dy6(teaH)6(NO3)6]·8MeOH is with B0 = 574.3(5) T characteristic for Dy(III) with a 6H15/2 ground state. The ligand substituted compound [Dy6(Me-teaH)6(NO3)6]·6MeCN possesses within the experimental errors the same magnetic hyperfine characteristics (B0 = 574.9(5) T). Consequently, the herein studied organic ligand variation has no perceptible influence on the magnetic hyperfine field sensed by the 161Dy(III) nuclei in these particular homometallic Dy(III)6-wheels. [ABSTRACT FROM AUTHOR]