Comprehensive Spectroscopic Determination of the Crystal Field Splitting in an Erbium Single-Ion Magnet

Abstract

The electronic structure of a novel lanthanide-based single-ion magnet, {C(NH2)3}5[Er(CO3)4]·11H2O, was comprehensively studied by means of a large number of different spectroscopic techniques, including far-infrared, optical, and magnetic resonance spectroscopies. A thorough analysis, based on crystal field theory, allowed an unambiguous determination of all relevant free ion and crystal field parameters. We show that inclusion of methods sensitive to the nature of the lowest-energy states is essential to arrive at a correct description of the states that are most relevant for the static and dynamic magnetic properties. The spectroscopic investigations also allowed for a full understanding of the magnetic relaxation processes occurring in this system. Thus, the importance of spectroscopic studies for the improvement of single-molecule magnets is underlined.

Magneto-Luminescence Correlation in the Textbook Dysprosium(III) Nitrate Single-Ion Magnet

“…This confirms that the main source of relaxation is clearly an Orbach process (red dashed line, Figure 5b). This constitutes a rare example of a luminescent SIM without an underestimation of ∆ obtained by magnetism as frequently observed in luminescent SIMs [7][8][9][10][11][12][13][14][15][16][17][18].…”

“…In this line of scope, luminescent SIMs are particularly appropriate for these investigations since the photo-luminescence measurements permit determining spectroscopically the Stark sub-level structure of the lanthanides ions and comparing it with the magnetic data. However, examples of such magneto-optical correlations are rather scarce [7][8][9][10][11][12][13][14][15][16][17][18] in comparison with the large number of reported lanthanides-based SIMs. This fact is often due to the weak or completely quenched emission in these complexes.…”

Molecular single-ion magnets based on lanthanides and actinides: Design considerations and new advances in the context of quantum technologies

“…These processes can be distinguished by characteristic magnetisation relaxation rates as a function of temperature (Eq. 2) [44]:…”

“…A promising and fundamentally different approach was proposed in 2003 by Ishikawa and co-workers [14], who successfully demonstrated that slow magnetic relaxation could occur in mononuclear lanthanide complexes, such as those in which a lanthanide (Ln) ion is sandwiched between two phthalocyanine (Pc) ligands, (Bu4N)[LnPc2] (Ln = Tb III (1), or Dy III (2), Bu4N = tetrabutylammonium). This rather unexpected result marked the beginning of a new era in single-molecule magnetism, with many research groups investing a great deal of effort in trying to understand this behaviour [41][42][43][44][45][46][47]. Real progress has been made in determining which factors affect most significantly the spin dynamics of Ln-SIMs [17,48].…”

Modelling spin Hamiltonian parameters of molecular nanomagnets

“…2 This is essentially due to the fact that these molecules possess several potential applications. The SMMs/SIMs show magnetic bistability 8 , which allows their magnetic moments to be positive or negative 9 and ensures their stability for prolonged time in zero external magnetic field. 1c, 3 The term MNMs cover wide range of molecules exhibiting interesting magnetic behaviour such as monometallic complexes exhibiting Single Ion Magnetic behaviour (SIMs), 4 multinuclear clusters exhibiting Single Molecule Magnets (SMMs) 1a, 5 behaviour, one dimensional coordination polymers exhibiting Single Chain Magnets (SCMs) 6 to molecular wheels 7 showcasing QPI phenomena.…”