Using internal strain and mass to modulate Dy⋯Dy coupling and relaxation of magnetization in heterobimetallic metallofullerenes DyM₂N@C₈₀and Dy₂MN@C₈₀(M = Sc, Y, La, Lu)

Abstract

Endohedral clusters inside metallofullerenes experience considerable inner strain when the size of the hosting cage is comparably small. This strain can be tuned in mixed-metal metallofullerenes by combining metals of...

Endohedral metallofullerene molecular nanomagnets

“…3a and c, Table 1). 79 A similar conclusion was also obtained by Wang et al showing a larger opening of hysteresis in DyY 2 N@C 80 compared to that of DySc 2 N@C 80 . 81…”

“…3a and c, Table 1). 79 A similar conclusion was also obtained by Wang et al showing a larger opening of hysteresis in DyY 2 N@C 80 compared to that of DySc 2 N@C 80 . 81 In addition to the encapsulated diamagnetic metal that plays an important role in determining the single-ion anisotropy and thus the SMM properties of NCFs, the cage structure Fig.…”

“…86 The results indicate that despite the same magnetic ground state of Ho 3+ with | m J | = 8 in these molecules, chemical shifts and ligand fields are strongly dependent on the size of the M 3+ ion, which is consistent with the conclusion extracted from DyM 2 N@C 80 . 79 Furthermore, an interesting behavior was revealed for HoLu 2 N@C 80 , in which the encapsulated cluster can be oriented in a magnetic field since the Ho magnetic moment aligns along the Ho-N axis due to the strong ligand field. 87 Thus, a hopping motion of the cluster is possible upon applying external magnetic fields, and the activation energy associated with such a process can be determined for HoLu 2 N@C 80 as well as for TbSc 2 N@C 80 , providing insights into the cluster–cage binding interaction.…”

Covalency versus magnetic axiality in Nd molecular magnets: Nd-photoluminescence, strong ligand-field, and unprecedented nephelauxetic effect in fullerenes NdM2N@C80 (M = Sc, Lu, Y)

“…Our earlier ab initio studies of LF in conformers of various Dy-SMMs showed that the influence of the lanthanide coordination to the fullerene cage is noticeable but not decisive. 51,119,120 Unexpectedly, the situation found here for NdSc 2 N@C 80 is quite dissimilar. The Δ LF splitting of the 4 I 9/2 multiplet in different conformers varies from 690 to 1018 cm −1 , and even larger relative variation is found for Δ 1,2 , which spans from 80 to 470 cm −1 (Fig.…”

“…In contrast, the ab initio description of the isostructural DySc 2 N@C 80 is entirely consistent with expectations for a strongly axial ligand eld. 45,120 The ground state KD1 has 99.7% weight of the j±15/2i state and g x,y is less than 10 −4 , while g z = 19.84 (versus 20.00 expected for the pure m J = ±15/2 state). 120 The next three KDs of DySc 2 N@C 80 also have high contribution of one of the j±m J i states (>80%), and the principal z axes of their pseudospin g-tensors are nearly collinear.…”