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Two new NaI/CuI,II polynuclear compounds [(NaCu3((R,R)‐3‐MeOSalcy)2(NCO)2](1) and [(NaCu2(3‐MeOSalpn)(NCO)2] (2) have been synthesized using the Schiff base (SB) ligands, (R,R)‐3‐MeOSalcy=(R,R)–N,N′‐bis(3‐methoxysalicylidene)‐1,2‐diaminocyclohexane and 3‐MeOSalpn=N,N′‐bis(3‐methoxysalicylidene)‐1,3‐diaminopropane, respectively. Both complexes contain the rarely observed linear [Cu(NCO)2]− ion which links [{CuII(SB)}2Na]+ ions in 1 or [{CuII(SB)Na}2]2+ ions in 2 producing different linear chain topologies. The mixed valent CuI/IINa network in compound 1 allows for greater magnetic isolation of the paramagnetic ions as compared to compound 2, leading to differences in their EPR spectra. [ABSTRACT FROM AUTHOR]

A series of thirty six complexes obtained from acetonitrile solutions of Cu(NO3)2, Ln(NO3)3 and 2,2‐biyridine or 5,5‐dimethyl‐2,2‐bipyridine (Ln=La‐Yb excluding Pm) have been characterized. The crystals may be grouped into six types: Type‐I, [Cu(bpy)3][La(NO3)5(OH2)]; Type‐II, [Cu(bpy)3][Ln(NO3)5(OH2)] ⋅ 2CH3CN (Ln=Ce, Pr); Type‐IIa, [Cu(5,5‐dmbpy)3][Ln(NO3)5(OH2)] ⋅ 2CH3CN (Ln=La, Ce); Type‐III, [Cu(bpy)3][Ln(NO3)5] (Ln=Nd, Sm–Lu); Type‐IIIa [Cu(5,5‐dmbpy)3][Ln(NO3)5] (Ln=Pr, Nd, Sm‐Lu); Type‐IV, [Cu(5,5‐dmbpy)2(NO3)]2[Ln(NO3)5(OH2)]⋅CH3CN [Ln=La‐Nd, Sm‐Tb). The coordination numbers of the nitrato and aquonitrato lanthanide anions are 10 and 11, respectively. The tris‐chelates in Types I, II and IIIa undergo static Jahn‐Teller distortion while Types IIa and III support fluxional tris‐chelate ions. Type‐IV contains distortion isomers of [Cu(5,5‐dmbpy)2NO3]+. The structural trends are analysed in terms of lanthanide contraction and non‐covalent interactions in the crystals. EPR and electronic spectral characteristics are discussed for the six types of compounds. [ABSTRACT FROM AUTHOR]

A series of thirteen complexes which may be formally considered as assembled from Cu(bpy)2(NO3)2 and Ln(NO3)3 (Ln=La−Yb excluding Pm, bpy=2,2'‐bipyridine) have been characterized. The crystals may be grouped into four classes: A, [Cu2(bpy)4(μ‐NO3)][Ln(NO3)6] (Ln=La−Nd); B, [Cu(bpy)2(NO3)]2[Ln(NO3)4(OH2)2](NO3) (Ln=Sm−Dy); C, [Cu(bpy)2(NO3)]2[Ln(NO3)5] (Ln=Ho−Tm); D, [Cu(bpy)2(NO3)]2 [Ln(NO3)3(OH2)3](NO3)2⋅2H2O (Ln=Yb). The coordination numbers of the nitrato or aquonitrato lanthanide anions range from 9 to 12. The dinuclear cation in Class A having a linear monoatomic nitrate bridge is new and is seen to produce weak antiferromagnetic coupling in these compounds. The other classes contain distortion isomers of [Cu(bpy)2NO3]+. The structural trends are analysed in terms of lanthanide contraction and non‐covalent interactions in the crystals. EPR and electronic spectral characteristics are discussed for the four classes of compounds. Self assembly from acetonitrile solutions containing 2,2‐bipyridine and hydrates of Cu(NO3)2 and Ln(NO3)3 results in 13 CuII‐LnIII compounds belonging to four classes. The structural trends including the formation of the new dinuclear Cu(II) complex having linear monoatomic nitrato bridge as well as the unusual cocrystal of neutral lanthanide aquanitrate with Cu(II) complex salt are analysed in terms of lanthanide contraction and non‐covalent interactions in the crystals. Magnetic properties, EPR and electronic spectral characteristics are also discussed. [ABSTRACT FROM AUTHOR]

Two new triply bridged Cu(II) compounds [Cu3(bpy)2(μ‐ClCH2COO)6] (1) and [Cu2(bpy)2(μ‐OH)(μ‐OH2)(μ‐ClCH2COO)](ClO4)2 (2) (where, bpy=2,2'‐bipyridine) have been synthesized and their magnetic properties have been measured and correlated with structure. Compound 1 is a novel centrosymmetric tricopper compound with only carboxylate bridges. The terminal Cu2+ ions have [5 + 1] coordination while the central ion has [4 + 2] coordination. The three centres are antiferromagnetically coupled, the exchange parameters for the neighbouring and distant pairs of Cu(II) atoms being 2 J=–28.6 cm–1 and 2 J'=–1.0 cm–1, respectively. In compound 2 three types bridging modes are observed, viz., hydroxo, aquo and carboxylato. The two Cu(II) centers are ferromagnetically coupled (2 J=73.8 cm–1) as previously observed for several di‐copper complexes with the same bridges. DFT calculations are in reasonable agreement with the magnetic exchange parameters for both dinuclear and trinuclear compounds. [Cu3(bpy)2(μ‐ClCH2COO)6] (1) and [Cu2(bpy)2(μ‐OH)(μ‐OH2)(μ‐ClCH2COO)](ClO4)2 (2) are two new triply bridged Cu(II) compounds. Compound 1 is a novel centrosymmetric tricopper compound with only carboxylate bridges and is antiferromagnetic while 2 is ferromagnetic. Their magnetic properties are correlated with structure and modeled well using DFT calculations. [ABSTRACT FROM AUTHOR]

Abstract: Five new chiral MnIII complexes [Mn((1R, 2R)‐Salcy)N3]∞⋅CH3CN (1), [Mn((R,R)‐Salcy)N3]∞ (2), [Mn((R,R)‐Salcy)N3] (4), [Mn((R,R)‐Salcy)(H2O)N3]⋅C4H8O (5) and [Mn((R,R)‐Salcy)NCS] (6) have been synthesized and characterized by X‐ray structural analysis and magnetic measurements (Salcy=N,N′‐bis(salicylidene)‐1,2‐diaminocyclohexane}. The four azido complexes have been obtained from the previously known [Mn((R,R)‐Salcy)(CH3OH)N3] (3) by crystallization from various solvents. Compounds 1 and 2 are trans‐μ‐1,3‐azide bridged coordination polymers. While 1 forms helical chains, the chain in 2 is formed via translation of a dimeric helicate repeat unit. Compound 3 is a methanol coordinated mononuclear azido complex which forms a 2D‐network through H‐bonding. Compounds 4 and 6 are phenoxo‐bridged dimers without inversion center. Compound 5 is an aqua coordinated mononuclear azido complex, which forms a 1D‐chain through O−H⋅⋅⋅N hydrogen bonding involving axial ligands. In all six compounds MnIII exhibits a characteristic Jahn−Teller elongation. The magnetic coupling in 1 and 2 leads to antiferromagnetic interaction along the chain (2 J=−11.6 cm−1 for 1 and –11.9 cm−1 for 2) through the μ‐1,3‐azide bridge. Compound 3 is weakly antiferromagnetic due to hydrogen bonding interactions in the lattice. The phenoxo dimers (4 and 6) do not have measurable exchange interaction, the low temperature susceptibility being influenced mainly by zero‐field splitting. [ABSTRACT FROM AUTHOR]