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A series of 12 new metal–organic frameworks based on lanthanide cations (Ln = Nd, Sm–Dy), octahedral cluster anions [Re6S8(CN)6]4− or [Re6Se8(CN)6]4− and adipamide (adp) were synthesized under mild conditions in aqueous ethanol solutions. Compounds of the general composition Cs[Ln(adp)2{Re6Q8(CN)6}]·3H2O (Ln = Nd, Sm–Dy; Q = S or Se) crystallize in the hexagonal space group P6422. Despite the presence of solvate H2O molecules in structure cavities, the crystal structures revealed that the coordination environment of lanthanide cations in these 3D polymers did not contain H2O ligands. This rare feature is attributed to the combination of a bulk cluster anion and flexible adp molecules, which occupy the lanthanide coordination sphere to yield a stable lanthanide-based building block. This assumption was confirmed by synthesis of a second crystalline modification of the compound Cs[Nd(adp)2{Re6S8(CN)6}]·3H2O (orthorhombic space group Cccm). Luminescence studies evidence the presence of the typical red luminescence of hexarhenium cluster complexes and the absence of observable luminescence of lanthanide cations for all the compounds except the Nd derivatives. Magnetic data indicate very weak antiferromagnetic exchange interactions between paramagnetic Ln3+ centers.

The cubane chalcocyanide cluster anion [Re4Te4(CN)12]4− was used as a pre-made building block for construction of a series of seven new coordination polymers (CPs) based on cationic complexes of Ln3+ ions and 1,10-phenantroline (phen). Together with three previously known compounds of this type, 1D CPs based on [Re4Te4(CN)12]4− anion formed a representative series which includes ten compounds (Ln = La, Pr, Nd, Sm–Ho, Yb). The main structural motif in the new compounds is the 1D chains composed of alternating cluster anions and [Ln(H2O)n(phen)m]3+ cationic fragments. Topology of the chains was found to be independent from the ionic radius and coordination number of the lanthanide ion. However, different number and orientation of coordinated phen and H2O molecules in the coordination environment of the lanthanide ions led to formation of several types of the supramolecular structures formed by non-covalent interactions between H2O, phen and CN− ligands. Influence of coordination environment of the lanthanide ions and conditions of the synthesis to the supramolecular structures is discussed in this work as well as structural relations with 1D coordination polymers based on mononuclear cyanometallate building blocks.

Cluster compounds based on a new {Re3Mo3Se8}n core were obtained and studied. The polymeric solid K6[Re3Mo3Se8(CN)4(CN)2/2] (1) containing 24 cluster valence electrons (CVE) was isolated as a result of high-temperature reaction. Water-soluble salts K5[Re3Mo3Se8(CN)6]·11H2O (2) and Cs5[Re3Mo3Se8(CN)6]·H2O (3) were prepared from compound 1. Crystal structures of the diamagnetic compounds 2 and 3 contain a cluster anion [Re3Mo3Se8(CN)6]5- with a 22-electronic core {Re3Mo3Se8}+. Metathesis reaction followed by recrystallization from CH3CN yielded paramagnetic salt (Ph4P)4[Re3Mo3Se8(CN)6]·2CH3CN (4) containing the {Re3Mo3Se8}2+ core with 21 CVE. Cyclic voltammetry of the solution of 4 displayed three quasi-reversible waves with E1/2 = -0.325, -0.818 and -1.410 V vs. Ag/AgCl electrode indicating the presence of [Re3Mo3Se8(CN)6]4-/5-/6-/7- transitions. Electronic structure calculations showed that both mer- and fac-isomers of [Re3Mo3Se8(CN)6]n- clusters undergo great distortion when the number of CVE decreases.

Self-assembly reaction of [Re 4 Te 4 (CN) 12 ] 4– tetrahedral rhenium chalcocyanide cluster anions, Tm 3+ cations and 1,10-phenanthroline in an H 2 O/EtOH medium was investigated at different temperatures. Slow mixing of reagent solutions at the room temperature lead to formation of cluster compound ( 1 ) containing unique trimeric anionic fragment [{Tm(phen) (H 2 O) 4 }{Tm(phen) 2 (H 2 O) 3 }{Tm(phen) 2 (H 2 O) 2 }{Re 4 Te 4 (CN) 12 } 3 ] 3− ( A1 , phen = 1,10-phenanthroline). Oligomeric anion A1 shows an unusual U-shaped structure build from three cluster anions and three {Tm(phen) n (H 2 O) m } 3+ ( n = 1, 2; m = 2–4) complex cations linked to each other by C N Tm N C covalent bonds and two couples of short OH…N hydrogen bonds. At the elevated (80–100 °C) temperatures the initial reaction products were dissolved, however, further increase of temperature up to 150 °C resulted in formation of layered (2D) coordination polymer K[{Tm(phen) (H 2 O) 3 }{Re 4 Te 4 (CN) 12 }]·0.5H 2 O ( 2 ). In addition to the experimental and X-Ray structural analysis data, thermal decomposition of compounds is also discussed.

Cluster compounds based on a new {Re

The crystal structure of MoS2 was for the first time refined based on precise three-dimensional X-ray diffraction data collected from the synthesized single crystal. The results of the refinement using the Hansen—Coppens multipole model based on X-ray diffraction data and quantum chemical calculations for the molybdenum disulfide monolayer and single crystal were analyzed in terms of Bader’s quantum theory of Atoms in Molecules (QTAIM). An analysis of the bond critical points (bcp) for S...S attests to a weak van der Waals interaction having the energy of ∼1.25 kcal mol−1 per S...S contact and the binding energy of the layers of ∼7.5 kcal mol−1.

Novel coordination compound [Fe(HC(3,5-Mepz)3)2](NO3)2 is obtained by a reaction of Fe(NO3)2 with tris(3,5-dimethylpyrazol-1-yl)methane. The compound is characterized with magnetic susceptibility method, electronic (diffuse reflection) and IR spectroscopy and powder diffraction. According to temperature dependence μeff(T) the compound possesses spin-crossover 1A1 ⇔ 5T2 with hysteresis (Tc↑ = 231, Tc↓ = 227 K) accompanied by thermochromism (pink ⇔ colorless). A crystal structure of the compound was determined just before (T = 240 K, FeHS–N 2.14–2.18 A) and after (T = 123 K, FeLS–N 1.97–1.99 A) spin phase transition.

The synthesis and characterization of hybrid polymers combining organic P,P′ (dppe) or N,N′ (pyrazine) ligands and inorganic donors (P4S3) as cross-linkers between copper(I) halide aggregates is described. As a simple model system the reaction of a mixture of P4S3, PEt3, and CuX (X = Cl, Br, I) was studied. According to X-ray diffraction analysis, pseudotetrahedral monomers [CuX(PEt3)2(P4S3)] (1–3) were formed, in which P4S3 coordinates through the apical phosphorus atom. Layering a mixture of P4S3, Ph2PCH2CH2PPh2 (dppe), and toluene with CuCl in MeCN under diffusion conditions gives 1D-[CuCl(dppe)(MeCN)] (6), which contains (Cu2Cl2)2(μ-dppe)2 clusters linked by another dppe ligand. The analogous reaction with CuI gives 1D-[CuI(P4S3)(dppe)] (7), which is built up of alternating trans-(Cu2I2)(P4S3)2 units and dppe linkers. Hybrid polymers 2D-[CuX(P4S3)(dppe)] [X = Br (8), I (9)] are formed if CH2Cl2 is used instead of toluene. The 2D structures of 8 and 9 may be derived from that of 7 by connecting neighboring (CuX)(dppe) strands with pairs of inversely coordinated P4S3 cages. Replacement of dppe by pyrazine (pyz) yields 3D-[(CuCl)4(P4S3)2(pyz)] (10) and 3D-[(CuBr)3(P4S3)(pyz)] (12), respectively. The structure of 10 comprises a 3D network composed of alternating, linked 2D-[(CuCl)2(P4S3)] and 2D-[CuCl(pyz)] layers. The structure of 12 contains cradles built from opposing (CuBr)6 rings and pairwise pyz and P4S3 bridges. These cradles are organized into a 3D framework by condensation of the (CuBr)6 rings, and the layers formed are linked by additional pyz molecules. The resulting voids are occupied by toluene molecules. The behavior of P4S3 and P,P′ or N,N′ ligands as competitive building blocks is also expressed by the formation of binary P4S3/CuX or pyz/CuX polymers.

High-quality single crystals of the title compound are prepared from a mixture of molybdenum and a twofold excess of sulfur (quartz tube, 1250 °C, 96 h) and used to determine the crystal structure of the compound by precise three-dimensional single crystal XRD and quantum chemical DFT calculations.

The synthesis and characterization of [Cp°2Mo2P4S] (1) and [Cp°2Mo2P2S3] (2) (Cp° = 1-tBu-3,4-Me2C5H2) has been described. The reaction of 1 in CH2Cl2 with 2 equiv. of CuI in MeCN under diffusion conditions gave [(Cp°2Mo2P4S)3(CuI)4]n (6a). The crystal structure of 6a consists of helical substructures of opposed chirality which are formed by the coordination of two Cu2I2 rings to three phosphorus atoms of the cyclo-P4S middle deck of 1. The resulting helix is connected with four helices of the same chirality by front-backside P coordination of another 1 unit. Compound 6a can reversibly include or release CH2Cl2 molecules without loosing its crystalline character. Thus, storing crystals of 6a under CH2Cl2 results in the formation of 6a·0.55CH2Cl2 (6b), the unit cell volume increasing by 113.6 A3 per formula unit, while in high vacuum the unit cell volume of 6b decreases to the value of 6a. The reaction of 1 with CuI in the presence of P4S3 gave a mixture of two isomeric polymers 7 and 8 of composition [(Cp°2Mo2P4S)(P4S3)(CuI)2]n. The crystal structures of both compounds 7 and 8 contain linear strands of [1(CuI)2]n and [(P4S3)(CuI)2]n with planar Cu2I2 rings as common interface. A two-dimensional framework is formed by interpenetration of both types of strands. The analogous reaction of the mixture of [Cp*2Mo2P4S] (Cp* = C5Me5) and P4S3 with CuI gave [(Cp*2Mo2P4S)(P4S3)(CuI)2]n (9). Contrary to the structures of 7 and 8 in this compound coordination of adjacent P atoms of the η3-P3 ligand and the η2-PS dumbbell leads to the formation of one-dimensional ribbons.