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A series of Ba–MII complexes with allylmalonic acid anions (Amal) [BaMII(Amal)2(H2O)3]n (MII = Mn (1), Co (2), Cu (3), and Zn (4)) were synthesized by the reaction of the corresponding transition metal sulfates and barium allylmalonate. The complexes were characterized by IR and EPR spectroscopy, elemental analysis, magnetochemical and solid phase thermal decomposition studies as well as powder and single-crystal X-ray crystallography. The main structural block {MII(Amal)2(H2O)x} (x = 1 for M = Cu, x = 2 for M = Mn, Co, and Zn) in 1–4 is formed by two chelate allylmalonate anions and water molecule(s), which are surrounded by Ba2+ ions. The magnetic measurements of paramagnetic compounds revealed weak ferromagnetic interactions between copper(II) ions in 3, and slow magnetic relaxation in non-zero field (HDC = 1500 Oe) for 2. According to the TGA data of 1–4, they are decomposed via different pathways in the case of MnII, CoII, CuII, and ZnII since the metal ions catalyze different types of processes. However, all the complexes undergo polymerization of the allyl fragment. [ABSTRACT FROM AUTHOR]

The interaction of the pivalate complexes of iron(III), [Fe3O(Piv)6(H2O)3]·HPiv, and cadmium(II), [Cd(Piv)2], in Et2O resulted in one more type of "ferric wheel" family complex, namely [Fe8(Piv)16{Cd(Piv)2}(μ-OH)8]·Et2O (1). The complex is an octanuclear iron(III) wheel with a {Cd(Piv)2} moiety asymmetrically incorporated into the ring. [ABSTRACT FROM AUTHOR]

Compounds containing bis‐chelate dianionic blocks {M(3d)(cbdc)2}2– (M(3d)=VIVO, CuII) with cations VO2+ and Cu2+ chelated by two anions of dicarboxylic acid have been prepared as crystals when aqueous solutions of vanadyl sulfate VOSO4⋅3H2O or copper sulfate CuSO4⋅5H2O have been allowed to react with sulfates of d‐metals (MnII, CoII, NiII, ZnII, and CdII) and barium salt of cyclobutane‐1,1‐dicarboxylic acid (H2cbdc=C4H6(CO2H)2) in the 1:1:2 ratio. The nature of the M(3d) metal center has been found to influence on the structure of the heterometallic compounds formed. 1D polymers [M(VO)(cbdc)2(EtOH)2(H2O)3]n (M=Mn (1), Co (2), Ni (3)), molecular dinuclear complex [Zn(VO)(cbdc)2(H2O)5]⋅H2O (4), and 1D polymer {[Cd(VO)(cbdc)2(H2O)5]⋅H2O}n (5) are formed when M(3d)=VIVO, whereas in the case of the bis‐chelate block with the CuII atom, ionic compounds [M(H2O)6][Cu(cbdc)2(H2O)] (M=Mn (6), Co (7), Ni (8), Zn (9)) and 2D polymer {[CdCu(cbdc)2(H2O)2]⋅2H2O}n have been synthesized. The isolation of paramagnetic centers in compounds 1–10 is confirmed by magnetic measurements and EPR spectroscopy. The structure of M(3d)‐M heterometallic compounds (M(3d)=VO2+, Cu2+; M=Mn2+, Co2+, Ni2+, Zn2+, Cd2+) with cyclobutane‐1,1‐dicarboxylic acid anions is influenced not only by the nature of the heterometal M at the same M(3d) but also the nature of this M(3d) center, which forms a bis‐chelate block with two anions of substituted malonic acid. [ABSTRACT FROM AUTHOR]

The reaction of VOSO4 with K2cbdc (cbdc2– is cyclobutane‐1,1‐dicarboxylate anion) and Ln(NO3)3 (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Y, Er, Tm, Yb, Lu) yielded 17 novel heterometallic LnIII‐VIV compounds comprising stable bis‐chelate units {VIVO(cbdc)2(H2O)}. Three structural types of compounds are formed depending on the nature of the rare‐earth metal: 1D polymers {[Ln(VO)(cbdc)2(H2O)7]·0.5[VO(cbdc)2]}n (structural type I) [Ln = La (1), Ce (2)], 3D polymers {[KLn(VO)2(cbdc)4(H2O)9]·3.5H2O}n (structural type II) [Ln = La (3), Ce (4), Pr (5), Nd (6), Sm (7), Eu (8), Gd (9), Tb (10), Dy (11), Ho (12)] comprising trinuclear units {LnV2}, and octanuclear complexes {[KLn(VO)2(cbdc)4(H2O)11]·2H2O}2 (structural type III) [Ln = Y (13), Er (14), Tm (15), Yb (16), Lu (17)] containing dinuclear units {LnV}. Magnetic properties were investigated for all isolated compounds. The GdIII‐VIV compound has ferromagnetic and antiferromagnetic exchange interactions between isotropic VIV and GdIII ions. Calculations using the DFT method at the UB3LYP/6‐31G(d,p)/SDD level of theory were performed in order to explain the different nature of exchange interactions in two GdIII‐VIV pairs. The YbIII‐VIV complex displays single‐molecule magnet properties; the effective energy barrier was estimated at ΔEeff/kB = 26 K. The magnetic properties of LnIII‐VIV compounds with heavy lanthanide ions (LnIII = Er, Tm, Yb) were rationalized in terms of crystal‐field calculations for LnIII ions. Three structural types of heterometallic LnIII‐VIV substituted malonates were synthesized from the bis‐malonate vanadyl unit and were characterized by single‐crystal and powder XRD and by magnetic measurements. The structures of the new compounds depend on the nature of the rare‐earth metal: a decrease in the LnIII ionic radius is accompanied by a decrease in the nuclearity of the {LnIII‐VIV} unit. [ABSTRACT FROM AUTHOR]

Mononuclear {Cu(Me2mal)2}2- dianion has been used as a building block for the synthesis of six new coordination polymers: {Li2(H2O)2(µ-H2O)[Cu(µ4-Me2mal)(µ-Me2mal)]} n ( 1), {Na2(µ-EtOH)2[Cu(µ5-Me2mal)2]} n ( 2), {K8(µ-H2O)6[Cu(µ-H2O)(µ3-Me2mal)(µ6-Me2mal)]2[Cu2(µ5-Me2mal)4]} n ( 3), {K2M(H2O)5(µ-H2O)3[Cu(µ-Me2mal)(µ3-Me2mal)][Cu(µ-H2O)(µ-Me2mal)(µ3-Me2mal)]} n (M = MgII ( 4) or NiII ( 5); isostructural compounds), and {K4Co3(H2O)8(µ-H2O)4(µ3-OH)2[Cu(H2O)(µ-Me2mal)(µ3-Me2mal)]2[Cu(µ-H2O)(µ3-Me2mal)2]2} n ( 6). It was shown that the structures of the compounds depend on the nature and ionic radius of the heterometal. In particular, the dimensionality of the complexes increases from 1D to 2D and 3D with increasing radius of the s-metal in compounds 1, 2, and 3, respectively. Partial replacement of K+ in 3 by Mg2+, Ni2+, or Co2+ leads to the formation of heterometallic coordination polymers 4 and 5, with 2D structure, and 3D complex 6. The compounds were characterized by single-crystal X-ray diffraction and EPR spectroscopy, and the magnetic properties of compounds 1, 2, and 4- 6 were also studied. Further, the topological analysis of the structures and another 794 known mal-derivatives complexes from Cambridge Structural Database (CSD, version 5.36) was performed. The main regularities determining the coordination modes of ligands and metal cations in relation to structure topology have been established and are discussed. [ABSTRACT FROM AUTHOR]

Trinuclear copper(II) complex [Cu II 3 (bipy) 6 (μ 3 -CO 3 )][B 12 H 12 ] 2 ·4.5DMF·2H 2 O is isolated as a result of the redox reaction proceeding when [Ag I 2 B 12 H 12 ] was allowed to react with Cu I Cl in the presence of bipy. Crystal structure, magnetic properties, and EPR spectrum of the compound are studied. It has been found that in the range 300–2 K, magnetic moment decreases from 1.98 to 1.33 µ B with decreasing the temperature. In the EPR spectrum, the transition ΔM = ±3 transition is observed indicating the existence of the S  = 3/2 state. This transition is explained by the effect of fine coupling tensor which admixes the |−1/〉 state into the |3/2〉 state and the |1/2〉 state into the |−3/2〉 state. The EPR spectrum is simulated by the spin Hamiltonians for S  = 3/2 and S  = 1/2. [ABSTRACT FROM AUTHOR]

The interaction of the pivalate complexes of iron(iii), [Fe3O(Piv)6(H2O)3]·HPiv, and cadmium(ii), [Cd(Piv)2], in Et2O resulted in one more type of "ferric wheel" family complex, namely [Fe8(Piv)16{Cd(Piv)2}(μ-OH)8]·Et2O (1). The complex is an octanuclear iron(iii) wheel with a {Cd(Piv)2} moiety asymmetrically incorporated into the ring.