Magnetic anisotropy of Co^II–W^Vferromagnet: single crystal and ab initio study

The rationalized pathway from field-induced slow magnetic relaxation in CoII–WIV chains to single-chain magnetism in isotopological CoII–WV analogues

“…The room-temperature χ M T values per {Co II 2 W V } unit of 2 and 3 are 6.6 and 6.3 cm 3 mol −1 K, respectively, which lie within the range of 5.8–7.2 cm 3 mol −1 K expected for two uncoupled high-spin (HS) Co II centres ( S = 3/2) and one paramagnetic W V centre ( S = ½, with the average g W = 2.0). 66–69 The average g Co values are 2.59 for 2 and 2.51 for 3 , which are situated within the limits of 2.4–2.7, characteristic of the HS Co II complexes embedded in cyanido-bridged coordination systems. Upon cooling, the χ M T values slowly increase from 300 K to ca.…”

“…The g -value is 2.65 which is in the 2.4–2.7 range typical for cyanido-bridged coordination polymers based on these 3d metal complexes. 66–69 Upon cooling, the χ M T value gradually decreases down to 3.7 cm 3 mol −1 K at 1.8 K which can be mainly ascribed to the depopulation of energy levels arising from spin–orbit coupling and crystal-field effects of Co II centres without significant magnetic interactions. 70,71 This interpretation is supported by the field-dependence of magnetization at 1.8 K characterized by a featureless curve with the highest value of 4.5 μ B at 70 kOe.…”

“…To test this idea, we selected the [W IV/V (CN) 8 ] 4−/3− redox pair. In the case of W( v ) ( S = ½), these ions were suitable linkers for ferromagnetic and strongly anisotropic Co II –[W V (CN) 8 ] 3− systems, 46,53,66–68 while, for the case of W( iv ) ( S = 0), they were successfully employed for the functionalization of lanthanide-centred SMMs. 59,60 Herein, we report a unique strategy toward single-ion magnet-like and single-chain magnet effects tuned by the W-oxidation state enabling the formation of two types of coordination chains, {[Co II (bpp)(H 2 O)] 2 [W IV (CN) 8 ]}·6H 2 O ( 1 ) (bpp = 2,6-di(1-pyrazolyl)pyridine) and {[Co II (bpp)X 0.5 (H 2 O) 0.5 ] 2 [W V (CN) 8 ]}·2H 2 O (X = Cl ( 2 ), Br ( 3 )).…”

Manganese‐Octacyanidoniobate‐Based Ferrimagnet Possessing Bridging Ligands with Disulfide Bonds

“…[47,[58][59][60][61][62] Among the organic ligands used in octacyanidometallate-based magnets showing long-range magnetic ordering, the dpds ligand is significantly large in size (Table 4). [61,[108][109][110][111] Although the dpds ligand is bulky, it fits in the cyanido-bridged MnÀ Nb framework due to its bend shaped induced by the disulfide bond. Thus, dpds ligands can be Table 2.…”

Lanthanide Photoluminescence in Heterometallic Polycyanidometallate-Based Coordination Networks

“…Heterometallic polycyanidometallate-based coordination networks have been extensively studied in the last decades due to their extraordinary magnetic properties, including strong exchange coupling, long-range magnetic ordering, and strong magnetic anisotropy [25,26,34,35,36,37]. The other fascinating physical functionalities, such as photoinduced magnetic and magneto-optical phenomena, microporosity, catalytic activity, ferroelectricity, and ionic conductivity have been found for the cyanido-bridged coordination compounds [38,39,40,41,42].…”