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A new mononuclear europium complex incorporating the (+)‐di‐p‐toluoyl‐d‐tartaric acid (d‐H2DTTA) ligand, namely, catena‐poly[tris{μ2‐3‐carboxy‐2,3‐bis[(4‐methylphenyl)carbonyloxy]propanoato}tris(methanol)europium(III)], [Eu(C20H17O8)3(CH3OH)3]n, (I), has been synthesized and characterized by IR spectroscopy, elemental analysis, powder X‐ray diffraction and single‐crystal X‐ray diffraction analysis. The structure analysis indicates that complex (I) crystallizes in the trigonal space group R3 and exhibits an infinite one‐dimensional chain structure, in which the Eu3+ ion is surrounded by six O atoms from six d‐HDTTA− ligands and three O atoms from three coordinated methanol molecules, thus forming a tricapped trigonal prism geometry. The d‐H2DTTA ligand is partially deprotonated and adopts a μ1,6‐coordination mode via two carboxylate groups to link adjacent Eu3+ ions, affording an infinite one‐dimensional propeller‐shaped coordination polymer chain along the c axis, with an Eu...Eu distance of 7.622 (1) Å. Moreover, C—H...π interactions lead to the formation of helical chains running along the c axis and the whole structure displays a snowflake pattern in the ab plane. The circular dichroism spectrum confirms the chirality of complex (I). The solid‐state photoluminescence properties were also investigated at room temperature and (I) exhibits characteristic red emission bands derived from the Eu3+ ion (CIE 0.63, 0.32), with a reasonably long lifetime of 0.394 ms, indicating effective energy transfer from the ligand to the metal centre. In addition, a magnetic investigation reveals single‐ion magnetic behaviour. The spin‐orbit coupling parameter (λ) between the ground and excited states is fitted to be 360 (2) cm−1 through Zeeman perturbation. Therefore, complex (I) may be regarded as a chiral optical‐magneto bifunctional material. [ABSTRACT FROM AUTHOR]

Five novel coordination polymers (CPs), formulated as {[Co3(μ4-cpboda)2(μ1,1-OH2)2(2,2-bipy)2]·1.5DMF·2H2O}n (1), {[Co3(μ3-cpboda)2(4,4′-bpy)3(H2O)2]·4H2O}n (2), {[Co(μ2-H2cpboda)2(1,4-bib)3(H2O)2]·H2O·DMF·1.5HCOOH}n (3), [Cd(μ3-Hcpboda)(1,4-bib)]n (4), and {[Cd3(μ4-cpboda)2(μ1,1-OH2)2(phen)2]·2DMF·1.5H2O}n (5) (H3cpboda = 3,3′-((5-carboxy-1,3-phenylene)bis(oxy))dibenzoic acid, 2,2-bipy = 2,2-bipyridine, 4,4′-bpy = 4,4′-bipyridine, 1,4-bib = 1,4-di(1H-imidazol-1-yl)benzene, phen = 1,10-phenanthroline) have been synthesized under solvothermal conditions and characterized by elemental analyses (EAs), single-crystal X-ray diffraction analyses, X-ray powder diffraction analyses (PXRD), FT-IR spectra, and thermogravimetric analyses (TGAs). The structural analyses reveal that these complexes have four 2D coordinate polymers and one 3D framework, in which metal ions are in octahedral coordination geometries in 1–3 and 5, but seven-coordinated disordered pentagonal bipyramids in 4. Complexes 1 and 5 represent linear trinuclear [M3(μ1,1-OH2)2(μ1,3-COO)4] SBUs in 1 (M = Co(ii)) and in 5 (M = Cd(ii)) based on a 3,4,6-connected net with a point symbol (32·4)2(32·83·9)2(34·42·82·94·103) net, complex 2 exhibiting a (3-c)2(4-c)(4-c)2 3D structure with the (52·6·82·9)2(52·62·92)(52·6)2 topology and complexes 3 and 4 having a novel 2D framework with the point symbol of (44·62). Magnetization analyses disclose the antiferromagnetic (AF) behaviors between Co(ii) ions in complexes 1 & 3 and S = 3/2 (Co2+) spin Heisenberg chains with alternating magnetic sequences (F/F/AF)n in 2. Fluorescence measurements indicate that 4 and 5 are promising luminescence sensors for the detection of CrO42− and Cr2O72− anions in aqueous solution. [ABSTRACT FROM AUTHOR]

Four new manganese(ii) metal–organic frameworks based on H4bpta (H4bpta = 3,3′,5,5′-biphenyltetracarboxylic acid) and N-donor ligands, namely [Mn2(4,4′-bipy)(bpta)]n (1), [Mn2(1,4-bib)2(bpta)]n·2n(H2O·DMF) (2), [Mn2(1,3-bimb)2(bpta)]n·2nH2O (3), and [Mn2(1,4-bimb)2(bpta)]n·2nH2O (4) (4,4′-bipy = 4,4′-bipyridine, 1,4-bib = 1,4-bis(imidazol-1-yl)benzene, 1,3-bimb = 1,3-bis((1H-imidazol-1-yl)methyl)benzene, and 1,4-bimb = 1,4-bis((1H-imidazol-1-yl)methyl)benzene), have been obtained under solvothermal conditions. In these complexes, the fully deprotonated bpta4− ligands link binuclear SBUs to construct 2D layers with (4,4)-connected topologies. Complex 1 is a 3D network with 1D zigzag chains built up from 4-connected bpta4− ligands that contain carboxylate groups bridging Mn2+ ions in a rather rare syn–syn geometry. Complex 2 exhibits a 3D porous network with syn–anti bridging dimeric subunits. Complex 3 is a (3,4)-connected 2D novel network with double helix chains formed by cis-1,3-bimb linkers. The structure of complex 4 is similar to that of 2, but it consists of tiny pores due to trans-1,4-bimb linkers. Magnetic studies reveal that 1 is perfectly fitted by the modified Fisher model to yield an effective intrachain antiferromagnetic coupling (J = −2.21(1) cm−1). Complexes 2–4 show antiferromagnetic interactions (J = −1.57(2) cm−1 for 2, and J = −0.68(2) cm−1 for 3) in dimeric units of Mn2(μ-COO)22+ related to double syn–anti and syn–syn carboxylate bridges. An important repetitive feature of all these complexes with syn–anti or syn–syn carboxylate bridges is that the antiferromagnetic coupling is very small. In addition, the gas sorption exploration of 2 exhibits relatively high sorption of CO2 but very low sorption of N2, making it a promising material for CO2/N2 separation. [ABSTRACT FROM AUTHOR]

The design and synthesis of coordination polymers (CPs) have attracted much interest due to the intriguing diversity of their architectures and topologies. The functional solid catena‐poly[μ2‐aqua‐triaqua{μ4‐5‐[4‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato}{μ3‐5‐[4‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato}dicobalt(II)], [Co2(C16H10O7)2(H2O)4]n or [Co2(HL)2(μ2‐H2O)(H2O)3]n, was synthesized successfully by self‐assembly of CoII ions with 5‐[(4‐carboxyphenoxy)methyl]isophthalic acid (H3L). The title compound was obtained under hydrothermal conditions and exhibits a twofold interpenetrated three‐dimensional skeleton with hms 3,5‐conn topology according to the cluster representation for valence‐bonded metal–organic frameworks (MOFs). It has been characterized by single‐crystal X‐ray diffraction, IR spectroscopy, powder X‐ray diffraction (PXRD), thermogravimetric analysis and susceptibility measurements. The antiferromagnetic coupling between adjacent CoII centres occurs via superexchange through the ligands. [ABSTRACT FROM AUTHOR]

Careful investigation of the effects of metal ions and pH value resulted in five multi-dimensional metal−organic complexes, [Co 5 ( μ 3 -OH) 2 ( α -bptc) 2 (H 2 O) 6 ] n ( 1 ), {(H 3 O) 2 [Co 4 ( μ 3 -O)( α -bptc) 2 (H 2 O)]·4H 2 O} n ( 2 ), {K 2 [Zn 4 ( μ 3 -OH) 2 ( α -bptc) 2 (H 2 O) 3 ]} n ( 3 ), [Zn 4 ( α -bptc) 2 (H 2 O) 3 ] n ( 4 ), and {[Cd 4 ( α -bptc) 2 (H 2 O) 7 ]·2H 2 O} n ( 5 ) ( α - H 4 bptc = 2,3,3 ' ,4 ' - biphenyl tetracarboxylic acid). The complexes consisted of different highly connected secondary building units (SBUs) assembled via hydrothermal in situ routes. The pH value as well as the kinds of metal ions influenced the coordination modes of α -H 4 bptc and also introduced the hydroxyl ligand at high pH value, resulting in the diversity of SBUs and dimensionality. Variable temperature magnetic measurements indicated the antiferromagnetic behavior in the Co 5 core in 1 , and the intra - chain ferrimagnetic behavior in complex 2 . Moreover, the luminescent properties of the complexes 3 − 5 indicated the existence of intra - ligand charge transfer. [ABSTRACT FROM AUTHOR]