Rational Design of Three-Dimensional (3D) Optically Active Molecule-Based Magnets:  Synthesis, Structure, Optical and Magnetic Properties of {[Ru(bpy)₃]²⁺, ClO₄^-, [Mn^IICr^III(ox)₃]^-}_nand {[Ru(bpy)₂ppy]⁺, [M^IICr^III(ox)₃]^-}_n, with M^II= Mn^II, Ni^II. X-ray Structure of {[ΔRu(bpy)₃]<

Abstract

To elucidate the relation between structural and magnetic properties, we have synthesized molecular materials having both Cotton effects and a ferromagnetic long range order. Such optically active 3D molecule-based magnets were rationally designed using the enantioselective template effect of optically active cations, namely Delta or Lambda [Ru(bpy)3, ClO4](+) or Delta or Lambda [Ru(bpy)3ppy](+) (bpy = bipyridine; ppy = phenylpyridine). Such cations are able to template the formation of optically active 3D anionic networks in which transition metal ions (Cr-Mn) and (Cr-Ni) are connected by oxalate ligands (ox). Following this strategy, we described the synthesis of ([Ru(bpy)3](2+), ClO4(-), [Mn(II)Cr(III)(ox)3](-))n and ([Ru(bpy)2ppy](+), [M(II)Cr(III)(ox)3](-))n with M(II) = Mn(II), Ni(II) in their optically active forms. In these 3D networks, all of the metallic centers have the same configuration, Delta or Lambda, as the template cation. We have determined the structure of ([DeltaRu(bpy)3][ClO4][DeltaMnDeltaCr(ox)3])n and ([LambdaRu(bpy)2ppy](+), [LambdaMn(II)LambdaCr(III)(ox)3](-))n by X-ray diffraction studies. These optically active networks show the Cotton effect and long-range ferromagnetic order at low temperatures. The magnetic circular dichroism of ([Ru(bpy)3](2+), ClO4(-), [Mn(II)Cr(III)(ox)3](-))n at 2 K is reported.

Synthesis, Crystal Structure, and Magnetic Properties of the Semihard Itinerant Ferromagnet RhFe3N

“…The results of the magnetization measurements before and after subtraction of the magnetic FeRh contribution are presented in Figure 3 in a plot of the atomic magnetic moment μ a per formula unit as a function of the temperature. On heating RhFe 3 N above 400 K one finds behavior typical of a ferromagnetic compound, and T C is estimated to be 505(25) K. ( T C is given by the intersection of the linear fit of the steepest part of the magnetization curve with the T axis 3031.…”

Structural and magnetic properties of two- and three-dimensional molecule-based magnets (cat)+[MIIMIII(C2O4)3]−

“…On the other hand, a homochiral arrangement ½M 1 ðDÞM 2 ðDÞ or ½M 1 ðLÞM 2 ðLÞ leads to a helical organization of the connected metallic ions. Therefore a three-dimensional anionic network is obtained with the associated cationic counter-part fitting in the vacancies of the anionic network [3].Exceptional is the X-ray structure of NPn 4 ½MnFeðoxÞ 3 ðPn ¼ n-C 5 H 11 Þ: In that case, the reaction leads to single crystals from the racemic materials to occur with a spontaneous chiral resolution of NPn 4 ½MnðDÞFeðLÞðoxÞ 3 and NPn 4 ½MnðLÞFeðDÞðoxÞ 3 enantiomers (space group C222 1 ) [4]. These results proved the existence of 2D networks in a chiral form.…”

“…On the other hand, a homochiral arrangement ½M 1 ðDÞM 2 ðDÞ or ½M 1 ðLÞM 2 ðLÞ leads to a helical organization of the connected metallic ions. Therefore a three-dimensional anionic network is obtained with the associated cationic counter-part fitting in the vacancies of the anionic network [3].…”

Materials Genome in Action: Identifying the Performance Limits of Physical Hydrogen Storage

“…86 An additional CoRE-MOF (CSD refcode: GUNFAW01) was found with mixed-metal vertices (chromium and manganese) linked with bipyridine and phenylpyridine that was originally designed to exhibit specific magnetic properties. 87 A contour plot of the predicted volumetric uptake for candidate GUNFAW01 across all temperatures and pressures can be found in Figure SI-9. The top candidates share common characteristics such as a void fraction close to 0.5 and a major pore diameter of around 10 Å, along with high surface areas above 3000 cm 2 /cm 3 and 5000 m 2 /g.…”