Hetero-Metallic {3d-4f-5d} Complexes: Preparation and Magnetic Behavior of Trinuclear [(L^Me2Ni−Ln){W(CN)₈}] Compounds (Ln = Gd, Tb, Dy, Ho, Er, Y; L^Me2 = Schiff base) and Variable SMM Characteristics for the Tb Derivative

Abstract

Assembling bimetallic {Ni-Ln}(3+) units and {W(CN)(8)}(3-) is shown to be an efficient route toward heteronuclear {3d-4f-5d} compounds. The reaction of either the binuclear [{L(Me2)Ni(H(2)O)(2)}{Ln(NO(3))(3)}] complexes or their mononuclear components [L(Me2)Ni] and Ln(NO(3))(3) with (HNBu(3))(3){W(CN)(8)} in dmf followed by diffusion of tetrahydrofuran yielded the trinuclear [{L(Me2)NiLn}{W(CN)(8)}] compounds 1 (Ln = Y), 2a,b (Gd), 3a,b (Tb), 4 (Dy), 5 (Ho), and 6 (Er) as crystalline materials. All of the derivatives possess the trinuclear core resulting from the linkage of the {W(CN)(8)} to the Ni center of the {Ni-Ln} unit. Differences are found in the solvent molecules acting as ligands and/or in the lattice depending on the crystallization conditions. For all the compounds ferromagnetic {Ni-W} and {Ni-Ln} (Ln = Gd, Tb, Dy, and Er} interactions are operative resulting in high spin ground states. Parameterization of the magnetic behaviors for the Y and Gd derivatives confirmed the strong cyano-mediated {Ni-W} interaction (J(NiW) = 27.1 and 28.5 cm(-1)) compared to the {Ni-Gd} interaction (J(NiGd) = 2.17 cm(-1)). The characteristic features for slow relaxation of the magnetization are observed for two Tb derivatives, but these are modulated by the crystal phase. Analysis of the frequency dependence of the alternating current susceptibility data yielded U(eff)/k(B) = 15.3 K and tau(0) = 4.5 x 10(-7) s for one derivative whereas no maxima of chi(M)'' appear above 2 K for the second one.

Bi‐Compartmental Schiff‐Base with Peripheral Ester Functionalization: Synthesis and Magnetic Behavior of Bimetallic Zn‐Ln Complexes (Ln = Dy, Tb, Gd)

“…Evidence for the electronic effect of the ester group on the core atoms of the ligand was obtained by the reaction of ZnL COOMe with the Ln(NO 3 ) 3 salts. Although the coordination of the [O 2 O 2 ] compartment of the Schiff base to the Ln ion usually takes place in solvents such as alcohols, MeCN, and even dmf, this failed with the ester‐functionalized compound. Such behavior is consistent with a decrease in the basicity of the phenolate oxygen atoms as a result of the electron‐withdrawing nature of the ester groups located at the para position.…”

First Heterotrimetallic {3 d‐4 d‐4 f} Single Chain Magnet, Constructed from Anisotropic High‐Spin Heterometallic Nodes and Paramagnetic Spacers

“…[11] The versatility of the [(CuL) Crystal structure investigations revealed that compounds 1 and 2 are isomorphous (see the Experimental Section). We will describe here the structure details for the Gd derivative, 1, those for 2 are very similar (Supporting Information).…”

Mononuclear and heterometallic dinuclear, trinuclear and dimer-of-dinuclear complexes derived from single- and double-compartment Schiff base ligands having a less utilized diamine

“…Types of previous systems (a total of 11) from single-compartment ligands where the diamine counterpart is 2,2-dimethyl-1,3-diaminopropane are as follows: two dinuclear Cu II Zn II [1,44]; one trinuclear Cu II Mn II Cu II ; one trinuclear Cu II Cd II Cu II [30]; one dimer-of-dinuclear (Cu II Cu II ) 2 (linker is acetate) [22]; two dinuclear Ni II Zn II [45]; one dinuclear Ni II Co II [27]; one trinuclear Ni II Cu II Ni II ; one trinuclear Ni II Co II Ni II ; one trinuclear Ni II Mn II Ni II [23]. Types of previous systems (a total of 35) from double-compartment 3-methoxysalicylaldehyde-diamine ligands where the diamine counterpart is 2,2-dimethyl-1,3-diaminopropane are: one trinuclear Ni II Na I Ni II [7]; one trinuclear Cu II Ca II Cu II [8] based polymer (the linker is nitrate); two dinuclear Ni II Y III [39,40]; one dinuclear Ni II Y III based polymer (the linker is octacyanotungstate(V) [1]; one dinuclear Ni II La III based polymer (the linker is octacyanotungstate(V) [1]; four dinuclear Cu II Gd III [56,59,63,64]; five dinuclear Cu II Tb III [56,57,62,65]; two dinuclear Cu II Dy III [56,57]; two dinuclear Cu II Ho III [56,57]; two dinuclear Cu II Er III [56,57]; two dinuclear Ni II Gd III [39,60]; three dinuclear Ni II Tb III [39]; one dinuclear Ni II Dy III [39]; one dinuclear Ni II Ho III [39]; one dinuclear Ni II Er III [39]; one dinuclear Ni II Yb III [66]; one trinuclear Ni II Eu III Ni II [68]; one trinuclear Ni II Gd III Ni II [67]; one di...…”

“…In fact, varieties of systems have been reported on isolating a copper(II)/nickel(II) mononuclear compound from a single-/double-compartment ligand and then reacting that mononuclear compound with various second metal salts from different blocks of the periodic table. The second metal ion in those compounds include s-block metal ions (alkali and alkaline metal ions such as Li I , Na I , K I , Rb I , Cs I , Mg II , Ca II , Sr II , Ba II ) [2][3][4][5][6][7][8][9][10][11][12][13], p-block metal ions (such as Pb II , Bi III , Tl I ) [12][13][14][15][16][17][18], 3d-block metal ions (such as Cu II , Ni II , Co II , Fe II , Mn II ) [15,[19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38], 4d/5d-block metal ions (such as Y III ) [39,40], d 10 metal ions (such as Zn II , Cd II , Hg II , Ag I ) [10,30,[41]…”