Spectroscopic techniques to probe magnetic anisotropy and spin-phonon coupling in metal complexes

• Published in: Dalton transactions : an international journal of inorganic chemistry Vol. 53; no. 1; pp. 439 - 445
• Main Authors: Hand, Adam T, Watson-Sanders, Brandon D, Xue, Zi-Ling
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 05.03.2024
• Subjects: Coordination compounds; Coupling (molecular); Couplings; Data storage; Magnetic anisotropy; Magnetic properties; Magnetism; Magnets; Mathematical analysis; Phonons; Quantum phenomena; Spectra
• ISSN: 1477-9226; 1477-9234; 1477-9234
• DOI: 10.1039/d3dt03609j

Magnetism of molecular quantum materials such as single-molecule magnets (SMMs) has been actively studied for potential applications in the new generation of high-density data storage using SMMs and quantum information science. Magnetic anisotropy and spin-phonon coupling are two key properties of d- and f-metal complexes. Here, phonons refer to both intermolecular and intramolecular vibrations. Direct determination of magnetic anisotropy and experimental studies of spin-phonon coupling are critical to the understanding of molecular magnetism. This article discusses our recent approach in using three complementary techniques, far-IR and Raman magneto-spectroscopies (FIRMS and RaMS, respectively) and inelastic neutron scatterings (INS), to determine magnetic excited states. Spin-phonon couplings are observed in FIRMS and RaMS. DFT phonon calculations give energies and symmetries of phonons as well as calculated INS spectra which help identify magnetic peaks in experimental INS spectra. Magnetic anisotropy and spin-phonon coupling are key properties of single-molecule magnets. The use of far-IR and Raman magneto-spectroscopies (FIRMS and RaMS), and inelastic neutron scattering (INS) to determine the magnetic properties is highlighted.