A Trigonal‐Bipyramidal Cyanide Cluster with Single‐Molecule‐Magnet Behavior: Synthesis, Structure, and Magnetic Properties of {[Mn^II(tmphen)₂]₃[Mn^III(CN)₆]₂}

Abstract

Molecules that exhibit magnetic bistability, commonly referred to as single-molecule magnets (SMMs), are of high interest because of their unusual physical properties and potential applications in quantum computing.[1] In contrast to traditional magnets, which are characterized by the bulk ordering of spins within a 3D solid, SMM behavior arises from the intrinsic magnetic properties of the individual molecules. The signature of an SMM is a slow paramagnetic relaxation of the magnetization evidenced by a frequency-dependent outof-phase (c 00 m ) ac susceptibility signal and hysteretic behavior. The presence of an appreciable thermal barrier for reversing the magnetization is related to the combination of a large total spin ground state (S) and negative uniaxial anisotropy (D). 4 ], which displays a ground state of S = 10.[2] Since this discovery, a number of oxo-bridged clusters containing V, [3] Mn, [4][5][6] Fe, [7] Co, [8] and Ni [9] have also been shown to display SMM behavior. In all cases, the molecules that have longer paramagnetic relaxation times have values of S > 3 or higher and a negative D value.In considering the prospects for preparing non-oxide SMMs, we turned our attention to chemistry inspired by the face-centered Prussian-blue solids. The recognition that bimetallic Prussian-blue solids exhibit spontaneous magnetization at temperatures as high as 376 K [10] prompted an extrapolation of this chemistry to the realm of magnetic

Variation of Heterometallic Structural Motifs Based on [W(CN)8]3− Anions and MnII Ions as a Function of Synthetic Conditions

“…Complex 4 contains diamagnetic W IV centers but holds promise as a potential photomagnetic solid. Keywords: chain structures · crystal structure · cyanides · magnetic properties · molecular squares worth mentioning that the heptanuclear cluster [Cu II L] 6 8 (L = tris(2-aminoethyl)amine) exhibits interesting photomagnetic behavior based on reversible photoinduced electron transfer between Cu II and Mo IV ions. [6] Introduction of various blocking ligands directed at limiting the number of available coordinating sites on the M' 8 ] 3À anions.…”

“…Keywords: chain structures · crystal structure · cyanides · magnetic properties · molecular squares worth mentioning that the heptanuclear cluster [Cu II L] 6 8 (L = tris(2-aminoethyl)amine) exhibits interesting photomagnetic behavior based on reversible photoinduced electron transfer between Cu II and Mo IV ions. [6] Introduction of various blocking ligands directed at limiting the number of available coordinating sites on the M' 8 ] 3À anions. [26,27] An examination of the existing structures revealed, however, that neither of the known compounds contained a trisdentate meridional blocking ligand of the 2,2':6',2''-terpyridine (terpy) type.…”

“…[4] Over the last decade, research in this area has produced coordination polymers and multinuclear clusters with diverse and interesting properties such as photoinduced magnetism, [5,6] single-molecule magnetism, [7][8][9][10][11][12][13] spin crossover, [14][15][16][17] and charge transfer induced spin transition. [18,19] With few exceptions, the cyanide containing precursor in the aforementioned chemistry is a homoleptic hexacyanometalate anion.…”

Unusual Magnetic Metal–Cyanide Cubes of ReII with Alternating Octahedral and Tetrahedral Corners

“…This "superparamagnetic-like" magnetic behavior of molecules, commonly referred to as "single-molecule magnetism", [5][6][7][8][9][10][11] has been observed for paramagnetic clusters that exhibit a large spin ground state combined with an appreciable degree of anisotropy (i.e., a negative zero-field splitting parameter D). [5,6,10,11] Singlemolecule magnet (SMM) behavior was first noted over ten years ago for an {Mn 12 } cluster of the oxide family, [10,11] and many new examples of oxide-based SMMs have been prepared in the ensuing years. [10,12] Progress in this area has been only incremental, however, in terms of raising the blocking temperature of the magnetization.…”

Magnetism and Photomagnetism of Prussian Blue Analogue Nanoparticles Embedded in Porous Metal Oxide Ordered Nanostructures

“…Most PBAs are magnets, and the versatility of their chemistry has allowed the magnetic ordering temperature to be pushed from 5 K in Prussian blue (Fe 4 [Fe(CN) 6 ] 3 ·nH 2 O) to room temperature in a VCr analogue. [2][3][4] They also served as a starting point for the development of cyanide-based single-molecule magnets [14] and single-chain magnets. [12] The second research stream deals with the study of compounds that can be switched between two or several electronic states with different magnetic properties in response to external stimuli.…”