Magnetic field and dilution effects on the slow relaxation of {Er₃} triangle-based arsenotungstate single-molecule magnets

Abstract

A triangular {Er3} cluster containing polyoxometalate (POM), [Er3(μ3-OH)(H2O)8(AsW9O33)(AsW10O35(DL-mal))]222− (1) (mal = malate), has been obtained via one-pot reactions. Structural analyses demonstrate that three Er3+ ions bridged one μ3-OH to generate...

Mononuclear Lanthanide Complexes in Triangular Dodecahedron Geometry: Manifestation of Single Ion Magnet Behavior for DyIII Analogue

“…It worth noting that the χ M T values of two complexes fall steadily with cooling before dropping rapidly to just 9.33 cm 3 K mol –1 for complex 1 and 4.43 cm 3 K mol –1 for complex 2 at 2 K, respectively. The decrease in χ M T value can be attributed to the progressive depopulation of the Dy III /Er III ion excited Stark sublevels and/or the possible intermolecular antiferromagnetic interactions between neighboring Dy III /Er III ions at low temperature. , …”

Luminescent Dimeric Oxalate-Bridged Eu3+/Tb3+-Implanted Arsenotungstates: Tunable Emission, Energy Transfer, and Detection of Ba2+ Ion in Aqueous Solution

“…Meanwhile, massive research efforts have been focusing on Tb and Eu mixed-Ln compounds which stem from their visible linelike emission, long lifetime, and efficient energy transfer (ET). − For example, some Eu/Tb-doped compounds are capable of achieving tunable emitting colors from green to red upon UV irradiation driven by the Tb 3+ → Eu 3+ ET process, thereby making them promising light-emitting materials . The exploration of Ln cations reacting with lacunary polyoxometalate (POM) units has been a widely used strategy to implement Ln-POM compounds, since Ln 3+ ions can easily react with different POM units by means of the stronger affinity for the surface oxygen atoms of POM. − As an important branch of POMs, the arsenotungstates have been attracting considerable attention due to their fascinating structural diversity as well as their wide application prospects. − Meanwhile, the introduction of Ln 3+ ions into lacunary arsenotungstates has been proven to be an effective strategy to build up Ln-implanted arsenotungstates with novel luminescence and magnetic properties. − …”

Oxalate-bridging NdIII-based arsenotungstate with multifunctional NIR-luminescence and magnetic properties

“…Nevertheless, most of these studies focus solely on the photoluminescence (PL) properties of Ln-POM derivatives, [20][21][22][23][24][25][26][27][28] although there are a few examples demonstrating SMM behaviors. [29][30][31][32][33][34] It is becoming widely accepted that the coordination environment of the Ln center has a great influence on the dynamic relaxation processes of Ln-SMMs. [35][36][37][38][39][40][41] Therefore, several ligands have been reported to coordinate with Ln cations and their effects on magnetic behaviors have been investigated.…”

“…31 Very recently, our group obtained a novel μ 3 -O-capped {Er 3 } cluster containing the POM K 20 O, which displays field-induced SMM behavior with two magnetic relaxation processes. 34 In particular, Nd-based SMMs are relatively less studied, [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61] with only two successful examples of Nd-POM SMMs having being reported to date. 62,63 In detail, Baldoví et al reported the first example of the structure of the Nd-POM singleion magnet [Nd(W 5 O 18 ) 2 ] 9− with an effective barrier of 51.4 cm −1 under an applied field in 2014.…”

“…31 Very recently, our group obtained a novel μ 3 -O-capped {Er 3 } cluster containing the POM K 20 Li 2 [Er 3 (μ 3 -OH)(H 2 O) 8 (AsW 9 O 33 )(AsW 10 O 35 (DL-mal))] 2 ·51H 2 O, which displays field-induced SMM behavior with two magnetic relaxation processes. 34…”