Highly ordered mesoporous Co 3 O 4 nanostructures were prepared using LP-FDU-12 as hard templates. By changing the hydrothermal temperature or by the acid treatment of the LP-FDU-12 template, Co 3 O 4 replicas with different cell parameters and wall thicknesses have been obtained. The structure and textural characteristics of both LP-FDU-12 and Co 3 O 4 replicas were investigated by X-ray diffraction, transmission electron microscopy, and N 2 adsorption−desorption isotherm analysis. The cell parameter and wall thickness of a mesoporous Co 3 O 4 have been varied systematically within the ranges 30.4−33.9 and 24.8−18.2 nm, respectively, and the materials exhibit surface areas in the 29.6−52.9 m 2 g −1 range, while preserving a highly ordered 3D pore structure and highly crystalline walls. Most importantly, magnetic studies show that the factors which affect the magnetic behavior in the Co 3 O 4 nanosphere system are not only the sphere size but also the space-filled parameter at the nanoscale.

No abstract

The title mononuclear complex, [Eu(C7H5O3)2(NO3)(C12H8N2)2], is isostructural with those of other lanthanides. The Eu atom is in a pseudo-bicapped square-anti­prismatic geometry, formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and by six O atoms, four from two 2,6-dihy­droxy­benzoate (DHB) ligands and the other two from a nitrate anion. π–π stacking inter­actions between phen and DHB ligands [centroid–centroid distances = 3.5312 (19) and 3.8347 (16) Å], and between phen and phen ligands [face-to-face separation = 3.433 (4) Å] of adjacent complexes stabilize the crystal structure. Intra­molecular O—H⋯O hydrogen bonds are observed in the DHB ligands.

The title mononuclear complex, [Sm(C7H5O3)2(NO3)(C12H8N2)2], is isostructural with that of other lanthanides. The Sm atom is in a pseudo-bicapped square-anti­prismatic geometry, formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and by six O atoms, four from two 2,6-dihy­droxy­benzoate (DHB) ligands and the other two from a nitrate anion. π–π stacking inter­actions between phen and DHB ligands [centroid–centroid distance = 3.528 (4) and 3.812 (3) Å], and phen and phen ligands [face-to-face separation = 3.420 (10) Å] of adjacent complexes stabilize the crystal structure. Intra­molecular O—H⋯O hydrogen bonds are observed in the DHB ligands.

Key indicators: single-crystal X-ray study; T = 298 K; mean (C-C) = 0.007 Å; R factor = 0.043; wR factor = 0.108; data-to-parameter ratio = 12.2.The mononuclear title complex, [Ce(C 7 H 5 O 3 ) 2 (NO 3 )-(C 12 H 8 N 2 ) 2 ], is isostructural to other related lanthanide structures. The Ce atom is in a pseudo-bicapped squareantiprismatic geometry formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and by six O atoms, four from two 2,6-dihydroxybenzoate (DHB) ligands and the other two from a nitrate anion. -stacking interactions between phen and DHB ligands [centroidcentroid distances = 3.513 (3) and 3.762 (2) Å ] and phen and phen ligands [face-to-face separation = 3.423 (7) Å ] of adjacent complexes stabilize the crystal structure. Intramolecular O-HÁ Á ÁO hydrogen bonds are observed in the DHB ligands. Related literature