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The preparation and physical characterization are reported for three Mn12 single-molecule magnets (SMMs) having naphthalenecarboxylate bridges, [Mn12O12(2-nc)16(H2O)4] (1, 2-ncH = 2-naphthalenecarboxylic acid), its Ph4P+ salt (2) and [Mn12O12(1-nc)16(H2O)4] (3, 1-ncH = 1-naphthalenecarboxylic acid). Complex 1·2CH2Cl2·4.5H2O crystallizes in the monoclinic space group C2/c, with cell dimensions at −160 °C of a = 28.524 Å, b = 17.819 Å, c = 36.058 Å, β = 92.399°, and Z = 4. The X-ray structure analysis of 1·2CH2Cl2·4.5H2O reveals that each [Mn12] molecule is connected to the neighboring molecules through eight π···π interactions to form a two-dimensional structure within the bc-plane. This is the first SMM that self-assembles two-dimensionally via π···π interaction. From Arrhenius plots of the frequency dependence of the temperatures of the χ″M peaks, the effective energy barriers Ueff for the reversal of the magnetization spin were estimated to be 61 K, 53 K, and 61 K for high-temperature phases of 1–3, respectively, and 31 K and 33 K for the low-temperature (LT) phases of 1 and 3, respectively. The analysis of the reduced magnetization data suggests that the LT phase of 1 has an S = 9 ground state with g = 1.998 and D = −0.61 K.

The title one-dimensional chain polymer complex, [Mn(C6H4NO3)Cl(C6H5N)2]n, was isolated from the reaction of MnCl2 with 6-oxo-1,6-dihydropyridine-2-carboxylic acid (HpicOH) in pyridine. The asymmetric unit contains one [Mn(HPicO)Cl(py)2] moiety (py is pyridine), with the (HpicO)- ligand acting in a tridentate manner via the two carboxylate O atoms and the pyridone O atom. The operation of inversion centres generates eight- and 14-membered rings and, in conjunction with an a-axis translation, leads to an infinite chain extending along [100]. The Mn...Mn separations in this chain are 5.1069 (6) and 7.1869 (6) A. The MnII atom has a distorted octahedral coordination, with trans-axial pyridine ligands and with three O atoms and the Cl atom in the equatorial plane. The conformation of the 14-membered ring is stabilized by pairs of inversion-related N-H...O hydrogen bonds.

The title compound, catena-poly[[chloridotetrakis(ethylenediamine-kappa(2)N,N')samarium(III)] [indium(III)-di-mu-tellurido-indium(III)-di-mu-tellurido]], {[SmCl(C(2)H(8)N(2))(4)][In(2)Te(4)]}(n), consists of a one-dimensional sinusoidal {[InTe(2)](-)}(n) anionic chain and [SmCl(en)(4)](2+) cations (en is ethylenediamine). The only other previously reported lanthanide analogue, viz. [LaCl(en)(4)][In(2)Te(4)], contains more usual linear one-dimensional {[InTe(2)](-)}(n) anion chains [Chen, Li, Chen & Proserpio (1998). Inorg. Chim. Acta, 273, 255-258]. The one-dimensional polymeric {[InTe(2)](-)}(n) chain is built of InTe(4) tetrahedra sharing opposite edges. The Sm(III) ion in the [SmCl(en)(4)](2+) cation is nine-coordinated by eight N atoms from four bidentate en molecules and by one chloride ion to form a monocapped square-antiprismatic geometry. The presence or absence of N-H...Cl hydrogen bonding is shown to affect the conformation of the anion.