Publication | Closed Access
Two Pairs of Chiral “Tower‐Like” Ln<sub>4</sub>Cr<sub>4</sub> (Ln=Gd, Dy) Clusters: Syntheses, Structure, and Magnetocaloric Effect
27
Citations
41
References
2018
Year
Two pairs of novel chiral chromium lanthanide compounds, formulated as l- and d-[Gd<sub>4</sub> Cr<sub>4</sub> (IN)<sub>10</sub> (μ<sub>3</sub> -OH)<sub>4</sub> (μ<sub>4</sub> -O)<sub>4</sub> (H<sub>2</sub> O)<sub>12</sub> ]⋅[IN]<sub>2</sub> ⋅8 H<sub>2</sub> O (1 and 3), and l- and d-[Dy<sub>4</sub> Cr<sub>4</sub> (IN)<sub>11</sub> (μ<sub>3</sub> -OH)<sub>4</sub> (μ<sub>4</sub> -O)<sub>4</sub> (H<sub>2</sub> O)<sub>8</sub> ]⋅[IN]⋅1.5 H<sub>2</sub> O (2 and 4) (HIN=isonicotinic acid) have been successfully synthesized and characterized. Structural analysis reveals that four Ln<sup>3+</sup> ions and four Cr<sup>3+</sup> ions connect with each other and yield a "tower-like" [Ln<sub>4</sub> Cr<sub>4</sub> ] skeleton. Apart from the above featuring an aesthetically charming structure, circular dichroism (CD) spectra confirm that compounds 1 and 3, 2 and 4 are enantiomers. To the best of our knowledge, these are the largest chiral chromium lanthanide compounds. In addition, magnetic interaction shows that Gd (the mixture of 1 and 3) exhibits significant cryogenic magnetocaloric effect (MCE) with -ΔS<sub>m</sub> =18.08 J kg<sup>-1</sup> K<sup>-1</sup> (34.69 mJ cm<sup>-3</sup> K<sup>-1</sup> ). Also, the observed second-harmonic generation efficiencies of [Gd<sub>4</sub> Cr<sub>4</sub> (IN)<sub>10</sub> (μ<sub>3</sub> -OH)<sub>4</sub> (μ<sub>4</sub> -O)<sub>4</sub> (H<sub>2</sub> O)<sub>12</sub> ]⋅[IN]<sub>2</sub> ⋅8 H<sub>2</sub> O and [Dy<sub>4</sub> Cr<sub>4</sub> (IN)<sub>11</sub> (μ<sub>3</sub> -OH)<sub>4</sub> (μ<sub>4</sub> -O)<sub>4</sub> (H<sub>2</sub> O)<sub>8</sub> ]⋅[IN]⋅1.5 H<sub>2</sub> O are 0.3 and 0.4 times that of urea, respectively.
| Year | Citations | |
|---|---|---|
Page 1
Page 1