C 42H32MnN10S6,t riclinic, P1 (no. 2), a =9.666(1) Å, b =11.077(2) Å, c =11.352(2) Å, a =87.663(2)°, Source of materialManganese(II) acetate tetrahydrate (0.123 g, 0.5 mmol) and NH 4 SCN (0.076 g, 1mmol) were refluxed in anhydrous methanol (10 mL) for 50 min, then were simultaneously added 20 mL methanol solution of freshly distilled salicylaldehyde and ethylenediamine at molar ratio 2:1.The mixture was stirred for 5h,4,4'-bipyridyl sulfide (0.11 g, 0.5 mmol) was added, the pH value was adjusted to 5with CH 3COOH solution, and the mixture was further stirred for 2h,then filtered. The resulting clear solution was diffused with diethyl ether vapor at room temperature for three weeks, yellow crystals were collected by filtration and dried in air (yield 0.156 g, 37 %

Source of materialZn(CH 3 COO) 2. · . 4H 2 O( 0.122 g, 0.5 mmol) and 4,4'-bipyridine (0.96 g, 0.5 mmol) were refluxed in anhydrous methanol (10 mL) for 50 min, then cyanoacetic acid (0.88 g, 1mmol) was added, the pH value was adjusted to 4with 0.5 MCH 3 COOH solution, and was further stirred for 2h,then filtered. The resulting clear solution was diffused with diethyl ether vapor at room temperature for two weeks, colourless crystals were obtained and collected by filtration and dried in air.

Source of materialThe mixture of 2,6-pyridinedicarboxylic acid (H 2 pydc, 0.0342 g, 0.2 .mmol) and (NH4)2C2O4.·.H2O( 0.0584 g, 0.4 mmol) in an aqueous solution (10 mL) of NaOH (0.008 g, 0.2 mmol) was added to the aqueous solution (10 mL) of Yb(NO 3 ) 3. · . 6H 2 O (0.190 g, 0.4 mmol), and the pH value was adjusted to 3w ith 0.2 .Mnitric acid solution. After stirring for 10 min in air the mixture was placed into 25 mL Teflon-lined autoclave and heated under autogenous pressure at 160°Cfor 72 h. The autoclave was cooled over aperiod of 12 hatarate 5°C/h. After the mixture was slowly cooled to room temperature, colourless crystals were obtained. The products are stable in air and insoluble in water (yield 0.017 g, 37 %based on Yb). IR data are available in the CIF. DiscussionCarboxylate ligands play an important role in constructing novel metal-organic frameworks (MOFs) based on lanthanides in coordination chemistry. They usually adopt diverse coordination modes such as terminal monodentate, chelating to one metal center, bridging bidentate in syn-syn, syn-anti,oranti-anti configurations to two metal centers [1][2][3]. Recently, some studies on di-and multi-carboxyl ligands or multi-functional carboxyl-containing ligands incorporating other coordination groups, such as N, S have been reported [4,5]. Among them imidazole di-or multicarboxylate have been intensively employed to provide ag reat variety of topological architectures [6,7]. On the other hand, oxalate ligand has been proven to be agood candidate for pillar ligand due to its various bridging abilities and strong coordination to metals to form 2D and 3D moderately robust networks exhibiting tunable ferro-or antiferromagnetic exchanges [8]. In contrast to a large number of lanthanide complexes containing only rigid or flexible multicarboxylate ligands, the rare homogeneous constructions involving nitrogen-heterocyclic carboxylate ions and oxalate ligand always only can be obtained from the in situ reaction, in which the multi-or dicarboxylic acid were decomposed into C 2 O 4 [9,10]. The asymmetric unit of the title complex consists of two Yb(III) cations, two pydc 2-ligands, one bridging oxalate group, six coordinated water molecules and five lattice water molecules. The Yb(III) is octa-coordinated with two oxygen atoms from the multichelating oxalate ligands, two oxygen atoms from the chelating carboxylate group of bpyc 2-ligand and three oxygen atoms from water molecules, as well as the nitrogen atom from the pyridyl ring, respectively. The Yb(III) exhibits ad istorted [YbO 8 ]t rigonal dodecahedral coordination polyhedron. The bond lengths of Yb-Orange from 2.286(3) to 2.348(3) Å,which are comparable to the distances observed in Yb(III) complexes with similar coordination spheres [11,12]. The oxalate anion acts as tetradentate bridge pillar to connect two adjacent Yb1 and Yb1A ions in a anti-anti mode, and thus affords adimer unit with the Yb···Yb separation of 6.069 Å.The pydc 2-ligand forms two five-membered Yb/N/C/C/O rings, as the ligands based on th...

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