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Comprehensive Summary: Three heteronuclear IrIII‐CoII arrays, [Co(H2O)6]2[Ir(ppyCOO)(ppyCOOH)(bpy)]2[Ir(ppyCOO)2(bpy)]2(NO3)2⋅10.5H2O (2), [Co(H2O)6]{Co(H2O)4[Ir(ppyCOO)2(bpy)]2}[Ir(ppyCOO)2(bpy)]2⋅15H2O (3) and {Co(H2O)2[Ir(ppyCOO)2(bpy)]2}⋅2CH3OH⋅3H2O (4), have been synthesized by combining paramagnetic CoII ion with luminescent IrIII‐metalloligand, [Ir(ppyCOOH)2(bpy)][Ir(ppyCOO)2(bpy)]⋅5H2O (1), where ppyCOOH = 3‐(pyridin‐2‐yl)benzoic acid and bpy = 2,2'‐bipyridyl. Owing to the variable charged states of compound 1 at different pH, compounds 2 and 3 are discrete ionic complexes containing hydrated Co2+ cations and deprotonated [Ir(ppyCOO)2(bpy)]– anions as well as coexisting neutral [Ir(ppyCOO)(ppyCOOH)(bpy)] (for 2) or Co(H2O)4[Ir(ppyCOO)2(bpy)]2 trinuclear molecule (for 3). Whereas compound 4 consists of self‐assembled two‐dimensional coordination polymer with Co‐metalloligand dative bonds. The hexa‐coordinated CoII cores in all complexes display octahedral geometries with varying degrees of distortion. In a bias dc field, the ac susceptibilities for 2—4 reveal slow magnetic relaxation. Moreover, the solid‐state phosphorescence is observed for compounds 2 and 3 due to weak supramolecular interaction between CoII ion and Ir‐moiety but is severely quenched for 4, where the Co center is strongly connected to the metalloligand. To the best of our knowledge, this is the first report of Ir‐Co systems showing both slow magnetization relaxation and photoluminescence. [ABSTRACT FROM AUTHOR]

The salts {[Ln2Ln*(Hhmq)3(OAc)3(hfac)2]+ [Ln*(hfac)3(OAc)(MeOH)]−} (Hhmq=2‐methanolquinolin‐8‐oxide, hfac=hexafluoroacetylacetonate; Ln, Ln*=Er, Gd, Yb) feature a discrete heteronuclear cation consisting of two types of lanthanide atoms. The quinolinoxy O‐atom serves as a μ2‐bridge to two Ln atoms and as a μ3‐bridge to all three atoms, with metal⋅⋅⋅metal distances being around 3.7 Å. For 1 ([Yb2Er]+), near‐infrared downshifted luminescence is switched to competitive upconversion luminescence upon irradiation by a 980 nm laser under an extremely low excitation power (0.288 W cm−2) through introduction of fluoride ions. The stability of 1 after addition of fluoride was confirmed by powder X‐ray diffraction and multistage mass spectrometry, associated with the 1H NMR of 6 ([La2Eu]+). More importantly, the at least 20‐fold enhancement of the quantum yield in non‐deuterated solvents at room temperature under low power densities (2 W cm−2) is the highest among the few molecular examples reported. [ABSTRACT FROM AUTHOR]

A composite material, {[Fe(L)(TPPE)0.5]⋅3 CH3OH}n, has been constructed by integrating the spin‐crossover (SCO) subunit FeII{diethyl(E,E)‐2,2′‐[1,2‐phenyl‐bis(iminomethylidyne)]bis(3‐oxobutanoate)‐(2‐)‐N,N′,O3,O3′} and the highly luminescent connector 1,1,2,2‐tetrakis(4‐(pyridin‐4‐yl)phenyl)‐ethene. Its structure contains four staggered 4×4 layers and intercalated methanol. The packing is dominated by considerable H‐bonds either between adjacent layers and between layers and guests. A crystal‐structure transformation was detected upon removal of the guest molecules. The SCO transition of the solvated crystals is centered at ca. 215 K with a non‐symmetrical hysteresis of 25 K wide, and the desolvated [Fe(L)(TPPE)0.5]n exhibits gradual SCO without hysteresis. Intriguingly, the intensity of the fluorescence at 460 nm for the latter is maximized at the SCO transition. The energy transfer between luminescent and SCO entities is achievable as confirmed by theoretical calculations. [ABSTRACT FROM AUTHOR]

The reaction of {(HNEt3)2[Ag10(tBuC6H4S)12]}n, Ag2O, Na2MoO4, and m‐methoxybenzoic acid (Hmbc) in CH3OH/CH2Cl2 led to yellow crystals of [Ag4S4 (MoO4)5@Ag66] (SD/Ag70b; SD=SunDi) only, while in the presence of DMF, additional dark‐red crystals of [Ag10@ (MoO4)7@Ag60] (SD/Ag70a) were obtained. SD/Ag70b consists of five MoO42− ions wrapped by a shell of 66 Ag atoms, while SD/Ag70a contains a rare Ag10 kernel consisting of five tetrahedra sharing faces and edges, surrounded by seven MoO42− ions enclosed in a shell of 60 Ag atoms. The formation of the Ag10 kernel originates from a reduction reaction during the self‐assembly process that involves DMF. This work provides the structural information of a unique Ag10 kernel (five fused Ag4 tetrahedra) and paves an avenue to trap elusive silver species with hierarchical multi‐shell silver nanocluster assemblies with the help of anion templates. [ABSTRACT FROM AUTHOR]

For ethene derivatives with large groups the cis‐isomer is often quite unstable and unavailable. Herein, we report an exception of two stable coordination complexes, (cis‐L)ZnCl2, starting from trans‐1,2‐bis(1‐R‐benzo[d]imidazol‐2‐yl)ethene (R=H, L1; R=CH3, L2) ligands under solvothermal condition (T ≥140 °C). Using the intensity of the absorption and luminescence spectra as probes we proposed its progressive cis‐to‐trans reversal upon irradiation with UV light, which was confirmed by powder X‐ray diffraction (PXRD). Similar results observed in the series of (cis‐L2)MIICl2 [M=Fe (4), Co (5), Ni (6)] demonstrate the universal strategy. The results of PXRD, NMR spectroscopy, ESI‐MS and DFT calculations support the above conclusion. NMR spectroscopy indicates that irradiation of 1 converts an optimized 71 % of the cis‐isomer to trans, whereas the free trans‐L1 ligand transforms to only 15 % cis‐isomer under similar conditions. Switch controller: Thermal treatment at 140 °C of trans‐L in the presence of MIICl2 (M=Fe, Co, Ni, Zn) led to stable (cis‐L)MCl2 and photoexcitation of the latter caused its transformation back to (trans‐L)MCl2(solvent). The kinetics can be followed by using UV/Vis absorption and luminescence. The results were confirmed by ESI‐MS, NMR spectroscopy, powder X‐ray diffraction and DFT calculations. [ABSTRACT FROM AUTHOR]

Cu(CF3COO)2 reacts with tert-butylacetylene ( tBuC≡CH) in methanol in the presence of metallic copper powder to give two air-stable clusters, [CuI15( tBuC≡C)10(CF3COO)5]⋅ tBuC≡CH ( 1) and [CuI16( tBuC≡C)12(CF3COO)4(CH3OH)2] ( 2). The assembly process involves in situ comproportionation reaction between Cu2+ and Cu0 and the formation of two different clusters is controlled by reactants concentration. The clusters consist of Cu15 and Cu16 cores co-stabilized by strong by σ- and π-bonded tert-butylethynide and CF3COO− (together with methanol molecule in 2). Their stabilities in solution were confirmed using electrospray ionization mass spectrometry in which the cluster core remains intact for 1 in chloroform and acetone, and for 2 in acetonitrile. Strong thermochromic luminescence in the near infrared (NIR) region was observed in the solid-state. Of particular interest, the emission maximum of 1 is red-shifted from 710 nm at 298 K to 793 nm at 93 K, along with a 17-fold fluorescence enhancement. In contrast, 2 exhibits red shift from 298 to 123 K followed by blue shift from 123 to 93 K. The emission wavelength was correlated with the structural parameters using variable-temperature X-ray single-crystal analyses. The rich cuprophilic interaction plays a significant role in the formation of 3LMCT ( tBuC≡C→Cux) excited state mixed with cluster-centered (3CC) characters, which can be considerably influenced by temperature, leading to thermochromic luminescence. The present work provides 1) a new synthetic protocol for the high-nuclear CuI-alkynyl clusters; 2) a comprehensive insight into the mechanism of thermochromic luminescence; 3) unusual emissive materials with the characters of NIR and thermochromic luminescence simultaneously. [ABSTRACT FROM AUTHOR]

A general class of C3-symmetric Ag9 clusters, [Ag9S( tBuC6H4S)6(dpph)3(CF3SO3)] ( 1), [Ag9( tBuC6H4S)6(dpph)3(CF3SO3)2] ⋅CF3SO3 ( 2), [Ag9( tBuC6H4S)6(dpph)3(NO3)2] ⋅NO3 ( 3), and [Ag9( tBuC6H4S)7(dpph)3(Mo2O7)0.5]2 ⋅2 CF3COO ( 4) (dpph=1,6-bis(diphenylphosphino)hexane), with a twisted trigonal-prism geometry was isolated by the reaction of polymeric {(HNEt3)2[Ag10( tBuC6H4S)12]} n, 1,6-bis(diphenylphosphino)hexane, and various silver salts under solvothermal conditions. The structures consist of discrete clusters constructed from a girdling Ag9 twisted trigonal prism with the top and bottom trigonal faces capped by diverse anions (i.e., S2− and CF3SO3− for compound 1, 2×CF3SO3− for compound 2, 2×NO3− for compound 3, and tBuC6H4S− and Mo2O72− for compound 4). This trigonal prism is bisected by another shrunken Ag3 trigon at its waist position. Interestingly, two inversion-related Ag9 trigonal-prismatic clusters are dimerized by the Mo2O72− ion in compound 4. The twist is amplified by the bulkier thiolate, which also introduces high steric-hindrance for the capping ligand, that is, the longer dpph ligand. Four more silver-sulfur clusters (namely, compounds 5- 8) with their nuclearity ranging from 6-10 were solely characterized by single-crystal X-ray diffraction to verify the above-described synergetic effect of mixed ligands in the construction of Ag9 twisted trigonal prisms. Surprisingly, only cluster 1 emits yellow luminescence at λ=584 nm at room temperature, which may be attributed to a charge transfer from the S 3p orbital to the Ag 5s orbital, or mixed with metal-centered (MC) d10→d9s1 transitions. Upon cooling from 300 to 80 K, the emission intensity was enhanced along with a hypsochromic shift. The good linear relationship between the maximum emission intensity and the temperature for compound 1 in the range of 180-300 K indicates that this is a promising molecular luminescent thermometer. Furthermore, cyclic voltammetric studies indicated that the diffusion- and surface-controlled redox processes were determined for compounds 1 and 3 as well as compound 4, respectively. [ABSTRACT FROM AUTHOR]

Cooperative effect: This cover artwork is inspired by the ancient Chinese myth of "King Yi Shooting Down Nine Suns". In the picture, bamboo represents the trans‐isomer of the ligand. After chelation of metallic ions with trans‐ligands under solvothermal condition, a cis‐LMIICl2 could be formed. Similarly, a bow, which stands for the cis‐LMIICl2, is made from pieces of bamboo and rope under hot temperatures. Just as the spectra discrepancy between cis‐LMIICl2 and trans‐isomer is sharply magnified, the bow can send arrows far away, as the legend goes, even to shoot the other nine suns down. More information can be found in the Full Paper by H.‐B. Xu, M.‐H. Zeng, et al. on page 5177. [ABSTRACT FROM AUTHOR]

Fourteen three-dimensional coordination polymers of general formula [Ln(INO)(H2O)(SO4)]n, where Ln = La, 1·La; Ce, 2·Ce; Pr, 3·Pr; Nd, 4·Nd; Sm, 5·Sm; Eu, 6·Eu; Gd, 7·Gd; Tb, 8&midddot;Tb; Dy, 9·Dy; Ho, 10·Ho; Er, 11·Er; Tm, 12·Tm; Yb, 13·Yb; and Lu, 14·Lu; INO =isonicotinate-N-oxide, have been synthesized by hydrothermal reactions of Ln3+, MnCO3, MnSO4·H2O, and isonicotinic acid N-oxide (HINO) at 155 °C and characterized by single-crystal X-ray diffraction, IR, thermal analysis, luminescence spectroscopy, and the magnetic measurement. The structures are formed by connection of layer, chain, or dimer of Ln-SO4 by the organic connector, INO. They belong to three structural types that are governed exclusively by the size of the ions: type I for the large ions, La, Ce, and Pr; type II for the medium ions, Nd, Sm, Eu, Gd, and Tb; and type III for the small ions, Dy, Ho, Er, Tm, Yb, and Lu. Type I consists of two-dimensional undulate Ln-sulfate layers pillared by INO to form a three-dimensional network. Type II has a 2-fold interpenetration of "3D herringbone" networks, in which the catenation is sustained by extensive π-π interactions and O-H…O and C-H…O hydrogen bonds. Type III comprises one-dimensional chains that are connected by INO bridges, resulting in an α-Po network. The progressive structural change is due to the metal coordination number decreasing from nine for the large ions via eight to seven for the small ions, demonstrating clearly the effect of lanthanide contraction. The sulfate ion acts as a μ4- or μ3-bridge, connecting two, three, or four metals, and is both mono- and bidentate. The INO ligand acts as a μ3- or μ2-bridge with carboxylate group in syn-syn bridging or bidentate chelating mode. The materials show considerably high thermal stability. The magnetic properties of 4·Nd, 6·Eu, 7·Gd, and 13·Yb and the luminescence properties of 6·Eu and 8·Th are also investigated. [ABSTRACT FROM AUTHOR]

A cadmium (II) coordination polymer, namely {[Cd5(Ln)6Cl4]·2H2O}n (1, HLn =1-methyl-2-(3H-[1–3]triazol-4-yl)-1H-benzoimidazole), has been constructed from in situ generated HLn under hydrothermal condition. The unsuccessful synthesis of 1 under similar synthesis condition using HLn as reactant suggests the in situ reaction is crucial for the assembly of the compound. Crystallography study reveals that 1 processes layer structure in which chains of [Cd3(Ln)4Cl4]2− were connected by a pair of Cd ions. These layers further stack in an AAA model to form a 3D supramolecular framework and hydrogen bonding as well as π–π interaction were formed between adjacent layers to stabilize the framework. TGA indicates that 1 is highly thermally stable up to about 380°C. The luminescence of 1 in the solid state which may be assigned to intraligand transition shows a blue shift of 16nm compared to that of HLn·HCl. [ABSTRACT FROM AUTHOR]