A family of lanthanide compounds based on nitronyl nitroxide radicals: synthesis, structure, magnetic and fluorescence properties

Abstract

A series of lanthanide nitronyl nitroxide radical compounds, [Ln(hfac)

Magnetic Improvement and Relaxation Mechanism of the Tb-Phthalocyanine Single-Molecule Magnet by Absorbing CH2Cl2 Molecules

“…The χ M values of TbPc 2 and TbPc 2 ·CH 2 Cl 2 are shown in Figure (a,b), respectively. The χ M T values of both TbPc 2 and TbPc 2 ·CH 2 Cl 2 increase rapidly with a continuous decrease in the temperature region below 50 K, implying that the magnetic dipole–dipole interactions between the Tb ions are ferromagnetic. ,, The magnetic interaction in the higher-temperature region can be analyzed by the Curie–Weiss law: Here, θ is the Weiss constant, which reflects the ferromagnetic or antiferromagnetic interaction corresponding to the positive or negative value, respectively, and C is the Curie constant. The fitting results give an estimated C value of 13.59 emu K/mol and a negative θ value of −2.70 K for TbPc 2 , and the C and θ values are 15.24 emu K/mol and −27.08 K for TbPc 2 ·CH 2 Cl 2 .…”

Luminescent Radicals

“…173 We also describe the luminescence of their lanthanide complexes (refs 169, 171, 61,150,152,154,160,161 or lanthanide-centered emissions. 177,181,[183][184][185]187,189 In the early 2000s, solid state emissions of NN and IN radicals were observed at cryogenic temperatures. [169][170][171]178 Figure 9 shows the absorption and emission spectra of IMImH and NITImH (Chart 5).…”

“…Since the early 2000s, the luminescence of these radicals has also been investigated (Chart ). ,,,,− ,− In the following, we introduce the luminescence properties of NN and IN radicals originating from (i) radical centers ,,,,,,,, and (ii) both radical centers and fluorescent substituents . We also describe the luminescence of their lanthanide complexes (refs , , , , and − ) in section in the next section.…”

“… ,,,,− ,− In the following, we introduce the luminescence properties of NN and IN radicals originating from (i) radical centers ,,,,,,,, and (ii) both radical centers and fluorescent substituents . We also describe the luminescence of their lanthanide complexes (refs , , , , and − ) in section in the next section. Various references report NN and IN radicals exhibiting only fluorophore-centered ,,,,, or lanthanide-centered emissions. ,,− ,, …”

Asymmetry-unit-dominated double slow-relaxation modes of 2,6-dimethyl-3,5-heptanedione dysprosium SMMs

“…S6 †), indicating the onset of pure QTM as oen seen in other dysprosium SMMs. [1][2][3][5][6][7][8][16][17][18][19][20][21] However, a temperature/ frequency dependence was observed below 16 K for complexes 2 and 3, although the QTM still exists below 5 K (Fig. 4 and S7 †).…”