Two diamond-type octacyanometallate(IV)–nickel(II) assemblies chelated by macrocyclic ligands

Two octacyanometallate-based Ni^II–M^IV [M?=?Mo(1), W(2)] bimetallic assemblies chelated with tetradentate macrocyclic ligands have been synthesized by slow diffusion and characterized structurally. In both complexes, M and Ni centers acting as linker and connector, respectively, are connected by M–CN–Ni–NC–M linkages to form a 3-D diamond-type topological network. Magnetic behaviors of both complexes show a very weak antiferromagnetic interaction between Ni^II ions mediated by the diamagnetic [M(CN)₈]^4? bridges.     

Diamond‐ and Graphite‐Like Octacyanometalate‐Based Polymers Induced by Metal Ions

By using cyclohexane‐1,2‐diamine (chxn), Ni(ClO₄)₂ ? 6H₂O and Na₃[Mo(CN)₈] ? 4H₂O, a 3D diamond‐like polymer {[Ni^II(chxn)₂]₂[Mo^IV(CN)₈] ? 8H₂O}_n ( 1 ) was synthesised, whereas the reaction of chxn and Cu(ClO₄)₂ ? 6H₂O with Na₃[M^V(CN)₈] ? 4H₂O (M=Mo, W) afforded two isomorphous graphite‐like complexes {[Cu^II(chxn)₂]₃[Mo^V(CN)₈]₂ ? 2H₂O}_n ( 2 ) and {[Cu^II(chxn)₂]₃[W^V(CN)₈]₂ ? 2H₂O}_n ( 3 ). When the same synthetic procedure was employed, but replacing Na₃[Mo(CN)₈] ? 4H₂O by (Bu₃NH)₃[Mo(CN)₈] ? 4H₂O (Bu₃N=tributylamine), {[Cu^II(chxn)₂Mo^IV(CN)₈][Cu^II(chxn)₂] ? 2H₂O}_n ( 4 ) was obtained. Single‐crystal X‐ray diffraction analyses showed that the framework of 4 is similar to 2 and 3 , except that a discrete [Cu(chxn)₂]²⁺ moiety in 4 possesses large channels of parallel adjacent layers. The experimental results showed that in this system, the diamond‐ or graphite‐like framework was strongly influenced by the inducement of metal ions. The magnetic properties illustrate that the diamagnetic [Mo^IV(CN)₈] bridges mediate very weak antiferromagnetic coupling between the Ni^II ions in 1 , but lead to the paramagnetic behaviour in 4 because [Mo^IV(CN)₈] weakly coordinates to the Cu^II ions. The magnetic investigations of 2 and 3 indicate the presence of ferromagnetic coupling between the Cu^II and W^V/Mo^V ions, and the more diffuse 5d orbitals lead to a stronger magnetic coupling interaction between the W^V and Cu^II ions than between the Mo^V and Cu^II ions.     

IV Dodekaedrische [Mo(CN)8]‐Koordination in den cyanoverbrückten Cobalt‐ und Nickel‐Amminkomplexen MII2(NH3)8[Mo(CN)8] · 1,5 H2O (MII = Co,Ni) und Ni2(NH3)9[Mo(CN)8] · 2 H2O

Crystal Structures of Octacyanomolybdates(IV). IV Dodecahedral [Mo(CN)₈] Coordination of the Cyano‐Bridged Cobalt and Nickel Ammin Complexes M^II₂(NH₃)₈[Mo(CN)₈] · 1.5 H₂O (M^II = Co, Ni) and Ni₂(NH₃)₉[Mo(CN)₈] · 2 H₂O At single crystals of the hydrated cyano complexes Co₂(NH₃)₈[Mo(CN)₈] · 1.5 H₂O (a = 910.0(4), b = 1671(2), c = 1501(1) pm, β = 93.76(6)°) and Ni₂(NH₃)₈[Mo(CN)₈] · 1.5 H₂O (a = 899.9(9), b = 1654.7(4), c = 1488(1) pm, β = 94.01°), isostructurally crystallizing in space group P2₁/c, Z = 4, and of trigonal Ni₂(NH₃)₉[Mo(CN)₈] · 2 H₂O (a = 955.1(1), c = 2326.7(7) pm, P3₁, Z = 3), X‐ray structure determinations were performed at 168 resp. 153 K. The [Mo(CN)₈]^4– groups of the three compounds, prepared at about 275 K and easily decomposing, show but slightly distorted dodecahedral coordination (mean distances Mo–C: 216.3, 215.4 and 216.1 pm). Within the monoclinic complexes the anions twodimensionally form cyano bridges to the ammin cations [M(NH₃)₄]²⁺ and are connected with the resulting [MN₆] octahedra (Co–N: 215.1 pm, Ni–N: 209.8 pm) into strongly puckered layers. The trigonal complex exhibits a chain structure, as one [Ni(NH₃)₅]²⁺ cation is only bound as terminal octahedron (Ni–N: 212.0 pm). Details and the influence of hydrogen bridges are discussed.     

Synthesis,crystal structures and magnetic properties of a series of new cyano-bridged complexes derived from templates [Ni(CN)4]2− and [Co(III)(CN)6]3−

Three new cyano-bridged complexes 1 [Ni(tn)₂Ni(CN)₄] (tn?=?1,3-diaminopropane), 2 [Cu^II(dipn)Ni^II(CN)₄], and 3 [Cu(dipn)]₆[Co(CN)₆]₄?·?4H₂O (dipn?=?dipropylenetriamine) have been assembled by the templates [Ni(CN)₄]^2? and [Co(CN)₆]^3?. 1 consists of a one-dimensional linear chain–Ni(tn)₂–NC–Ni(CN)₂–CN–Ni(tn)_2? in which the Ni(II) centers are linked by two CN groups. One 1-D zigzag chain of 2 is formed with–Ni(2)–C–N–Cu(1)–N–C–linkages. A 2D structure of 3 is formed by an alternate array of [Co(CN)₆]^3? and [Co][Cu₆] units. For 1, there is an overall weak antiferromagnetic interaction between Ni(II) ions through the–NC–Ni–CN–bridges of the diamagnetic [Ni(CN)₄]^2? anions. 2 exhibits a weak antiferromagnetic exchange interaction between copper(II) ions mediated by [Ni(CN)₄]^2? diamagnetic bridges. Complex 3 exhibits a weak ferromagnetic interaction between nearest Cu^II and Cu^II atoms through–NC–Co–CN–bridges.     

Syntheses,structures, and host-guest interactions of 2-D grid-type cyanide-bridged compounds [Zn(L)(H2O)2][M(CN)4]·3H2O (L = N,N′-bis(4-pyridylformamide)-1,4-benzene; M = Ni,Pd or Pt)

Self-assembly of Zn²⁺, the pillar ligand N,N′-bis(4-pyridylformamide)-1,4-benzene, and [M(CN)₄]^2? (M = Ni, Pd, or Pt) formed three compounds [Zn(L)(H₂O)₂][M(CN)₄]·3H₂O (1–3). Single-crystal X-ray diffraction (XRD) analysis reveals that 1–3 are isostructural and consist of cyanide-bridged 2-D grid-type layers built of [Zn(L)(H₂O)₂]²⁺ chains cross-linked by [M(CN)₄]^2? units. Thermogravimetric and powder XRD analyses indicate that 1 has a high thermal stability and exhibits reversibility for desorption/resorption of water guest molecules.     

Isolation and Structural Characterization of Eightfold Protonated Octacyanometalates [M(CNH)8]4+ (M=MoIV,WIV) from Superacids

Octacyanometalates K₄[Mo(CN)₈] and K₄[W(CN)₈] are completely protonated in superacidic mixtures of anhydrous hydrogen fluoride and antimony pentafluoride. The resulting hydrogen isocyanide complexes [Mo(CNH)₈]⁴⁺ [SbF₆]^?₄ and [W(CNH)₈]⁴⁺ [SbF₆]^?₄ are the first examples of eight‐coordinate homoleptic metal complexes containing hydrogen isocyanide (CNH) ligands. The complexes were crystallographically characterized, revealing hydrogen‐bonded networks with short N???H???F contacts. Low‐temperature NMR measurements in HF confirmed rapid proton exchange even at ?40 °C. Upon protonation, ν(C≡N) increases of about 50 cm^?1 which is in agreement with DFT calculations.     

Ni3 versus Ni30: A Truncated Octahedron Metal–Organic Cage Constructed with [Ni5(CN)4]6+ Squares and Tripodal Tris‐tacn Ligands That are Large and Flexible

Reactions of trinickel complex of tripodal tris‐tacn ligand N(CH₂‐m‐C₆H₄‐CH₂tacn)₃ ( L , tacn=1,4,7‐triazacyclononane) in acetonitrile–methanol solution with and without phosphate led to two complexes of distinct nuclearities, [(Ni^IICl)₃(CH₃OH)₃(HPO₄) L ](PF₆) (Ni₃, 1 ) and [(Ni^II₅(CN)₄(H₂O)₈Cl)₆ L ₈]Cl₃₀ (Ni₃₀, 2 ). Ligand L takes upward and downward conformation in the structure of 1 and 2 , respectively. It is proposed that phosphate directs the upward conformation of Ni₃ L to form 1 . In the absence of phosphate, Ni₃ L assembles with cyanide ions, which are formed by Ni‐catalyzed C?CN bond cleavage of acetonitrile, to give a nano‐sized Ni₃₀ cage. Complex 2 represents a discrete truncated octahedron cage assembled with [Ni₅(CN)₄]⁶⁺ squares and large and flexible triangular ligands, which is scarcely observed for self‐assembled metal‐organic cages. The magnetic properties of 1 and 2 were examined, showing intriguing magnetic properties.     

Three new homoleptic nickel(II) 1,1-dithiocarbamate complexes: synthesis,structure, electrical conductivity and DFT study

Abstract

Three new homoleptic complexes of nickel having the formula [Ni(L1)₂] [L1?=?C₁₄H₁₄N₁O₂S₂^-, N-(4-methoxybenzyl)(furfuryl)methane dithiocarbamate] (1), [Ni(L2)₂] [L2?=?C₁₇H₁₈N₁O₂S₂^–, N-bis(4-methoxybenzyl)methane dithiocarbamate] (2) and [Ni(L3)₂] [L3?=?C₁₉H₂₁N₁O₁S₂^-, N-(4-isopropylbenzyl)(4-methoxybenzyl)methane dithiocarbamate] (3), have been designed, synthesized, and characterized by elemental analysis, IR, ¹H and ¹³C NMR and UV-visible absorption spectra showing that all complexes having analogous geometry and coordination number. The molecular structure of 2 is confirmed by single-crystal X-ray crystallography, which indicates that +2 charges on the metal ion (Ni²⁺) are balanced by dithiocarbamate anion. The X-ray analysis for 2 reveals a distorted square planar geometry around Ni²⁺ ion. Both C?–?H···S and intermolecular C–H···Ni interactions are the only artifact for the resulting Ni-dithiocarbamate architecture in 2. The electrical conductivity measurement between temperatures range of 303–393 K reflects that all complexes exhibit weak semiconducting behavior. Powder XRD, EDAX, and SEM spectra confirm the formation of NiS as thermal decomposition product in 1–3. The crystalline size of samples 1–3 was found to be 20.31?nm, 20.97?nm, and 20.39?nm, respectively.     

Heterotrimetallic Coordination Polymers: {CuIILnIIIFeIII} Chains and {NiIILnIIIFeIII} Layers: Synthesis,Crystal Structures,and Magnetic Properties

The use of the [Fe^III(AA)(CN)₄]^? complex anion as metalloligand towards the preformed [Cu^II(valpn)Ln^III]³⁺ or [Ni^II(valpn)Ln^III]³⁺ heterometallic complex cations (AA=2,2′‐bipyridine (bipy) and 1,10‐phenathroline (phen); H₂valpn=1,3‐propanediyl‐bis(2‐iminomethylene‐6‐methoxyphenol)) allowed the preparation of two families of heterotrimetallic complexes: three isostructural 1D coordination polymers of general formula {[Cu^II(valpn)Ln^III(H₂O)₃(μ‐NC)₂Fe^III(phen)(CN)₂ {(μ‐NC)Fe^III(phen)(CN)₃}]NO₃ ? 7 H₂O}_n (Ln=Gd ( 1 ), Tb ( 2 ), and Dy ( 3 )) and the trinuclear complex [Cu^II(valpn)La^III(OH₂)₃(O₂NO)(μ‐NC)Fe^III(phen)(CN)₃] ? NO₃ ? H₂O ? CH₃CN ( 4 ) were obtained with the [Cu^II(valpn)Ln^III]³⁺ assembling unit, whereas three isostructural heterotrimetallic 2D networks, {[Ni^II(valpn)Ln^III(ONO₂)₂(H₂O)(μ‐NC)₃Fe^III(bipy)(CN)] ? 2 H₂O ? 2 CH₃CN}_n (Ln=Gd ( 5 ), Tb ( 6 ), and Dy ( 7 )) resulted with the related [Ni^II(valpn)Ln^III]³⁺ precursor. The crystal structure of compound 4 consists of discrete heterotrimetallic complex cations, [Cu^II(valpn)La^III(OH₂)₃(O₂NO)(μ‐NC)Fe^III(phen)(CN)₃]⁺, nitrate counterions, and non‐coordinate water and acetonitrile molecules. The heteroleptic {Fe^III(bipy)(CN)₄} moiety in 5 – 7 acts as a tris‐monodentate ligand towards three {Ni^II(valpn)Ln^III} binuclear nodes leading to heterotrimetallic 2D networks. The ferromagnetic interaction through the diphenoxo bridge in the Cu^II?Ln^III ( 1 – 3 ) and Ni^II?Ln^III ( 5 – 7 ) units, as well as through the single cyanide bridge between the Fe^III and either Ni^II ( 5 – 7 ) or Cu^II ( 4 ) account for the overall ferromagnetic behavior observed in 1 – 7 . DFT‐type calculations were performed to substantiate the magnetic interactions in 1 , 4 , and 5 . Interestingly, compound 6 exhibits slow relaxation of the magnetization with maxima of the out‐of‐phase ac signals below 4.0 K in the lack of a dc field, the values of the pre‐exponential factor (τ_o) and energy barrier (E_a) through the Arrhenius equation being 2.0×10^?12 s and 29.1 cm^?1, respectively. In the case of 7 , the ferromagnetic interactions through the double phenoxo (Ni^II–Dy^III) and single cyanide (Fe^III–Ni^II) pathways are masked by the depopulation of the Stark levels of the Dy^III ion, this feature most likely accounting for the continuous decrease of χ_M T upon cooling observed for this last compound.     

Capping [H<Subscript>8−n</Subscript>Ni<Subscript>42</Subscript>C<Subscript>8</Subscript>(CO)<Subscript>44</Subscript>]<Superscript>n−</Superscript> (n = 6, 7, 8) Octa-carbide Carbonyl Nanoclusters with [Ni(CO)] and [CuCl] Fragments

The reactions of [Ni₁₆(C₂)₂(CO)₂₃]^4? and [Ni₃₈C₆(CO)₄₂]^6? with CuCl afforded mixtures of the previously reported [HNi₄₂C₈(CO)₄₄(CuCl)]^7? bimetallic octa-carbide cluster and the new [HNi₄₃C₈(CO)₄₅]^7? and [HNi₄₄C₈(CO)₄₆]^7? homo-metallic octa-carbides. The three species have very similar properties resulting always in co-crystals such as [NMe₄]₇[HNi_42+2xC₈(CO)_44+2x(CuCl)_1?x]·6.5MeCN (x = 0.14) (86% [HNi₄₂C₈(CO)₄₄(CuCl)]^7?, 14%[HNi₄₃C₈(CO)₄₅]^7?/[HNi₄₄C₈(CO)₄₆]^7?) and [NMe₄]₇[HNi_42+2xC₈(CO)_44+2x(CuCl)_1?x]·5.5MeCN (x = 0.30) (70% [HNi₄₂C₈(CO)₄₄(CuCl)]^7?, 30% [HNi₄₃C₈(CO)₄₅]^7?/[HNi₄₄C₈(CO)₄₆]^7?). The new homo-metallic octa-carbides can be obtained free from the Ni–Cu octa-carbido cluster by reacting [Ni₁₀(C₂)(CO)₁₆]^2? in thf with a stoichiometric amount of CuCl, and crystals of [NMe₄]₆[H₂Ni_43+xC₈(CO)_45+x]·6MeCN (x = 0.72), which contain [H₂Ni₄₄C₈(CO)₄₆]^6? (72%) and [H₂Ni₄₃C₈(CO)₄₅]^6? (28%), have been obtained. Despite the different charges and compositions, these anions display almost identical structures, which are also closely related to those previously reported for the bimetallic Ni–Cd octa-carbido clusters [Ni_42+xC₈(CO)_44+x(CdCl)]^7? and [HNi_42+xC₈(CO)_44+x(CdBr)]^6?. Indeed, all these clusters are based on the same Ni₄₂C₈ cage decorated by miscellaneous [CdX]⁺ (X = Cl, Br), [CuCl] and [Ni(CO)] fragments.     

The influence of the nature of the ligand,L, on the electrochemical behaviour of dinitrosyl molybdenum complexes,Mo(NO)2L2Cl2, in aprotic media

Electrochemical investigations of the reduction of dicationic, monocationic and neutral dinitrosyl molybdenum complexes in nitromethane and acetonitrile are reported. All the compounds with the general formulae: [Mo(NO)₂L₂L′₂]²⁺, [Mo(NO)₂L₂L′Cl]⁺ and Mo(NO)₂L₂Cl₂ (L = CH₃CN, CH₂CHCN, C₆H₅CN, C₅H₅N, P(C₆H₅)₃, L₂ = 2,2′-bipyridine, L′ = CH₃CN and L′₂ = 2,2′-bipyridine) are reducible by one electron to yield 19-electron complexes. The dicationic complexes undergo a reversible one-electron transfer. For the mono- and dichlorocomplexes, the one-electron transfer induces the facile exchange of the chloroligand in the 19-electron complexes except for L₂ = 2,2′-bipyridine. However, the exchange of the chloroligand is followed by the fast anation by Cl^? of the remaining 18-electron chlorocomplexes to afford [Mo(NO)₂Cl₃L]^? and [Mo(NO)₂Cl₄]^2? which are reducible at higher negative potentials than dichloro- and monochlorocomplexes. The multiple electrochemical step system is not catalytic, but of the electroactivation type.     

Two octacyanomolybdate(IV)-M(II) (M = Mn,Co) bimetallic assemblies: Crystal structures and magnetic properties

Two cyano-bridged bimetallic complexes {[M₂(H₂O)₄Mo(CN)₈] · 4H₂O} _n [M = Mn (I) and Co (II)] have been synthesized and structurally characterized. The single-crystal X-ray analyses reveal that these two compounds have three-dimensional structures, and cell parameters are similar in a tetragonal system with space group I $ \bar 4 $ \bar 4 . In the both complexes, each [Mo(CN)₈]⁴⁻ building block is linked with M²⁺ [M = Mn and Co] ions through its eight CN ligands. Each M²⁺ center is connected to four Mo units forming a three-dimensional framework. In addition, magnetic studies of these complexes have been presented.     

Photokatalytische Systeme. LXVIII. Second-Sphere-Photoreaktion von Cyanometallaten mit Diphenyliodoniumionen

Photocatalytic Systems. LXVIII. Second-Sphere Photoreaction of Cyanometallates with Diphenyliodonium Ions Solutions of diphenyliodonium salts of [Ru(CN)₆]^4?, [Fe(CN)₅DMSO]^3?, [Mo(CN)₈]^4?, [Mn(CN)₅NO]^3?, [W(CN)₈]^4?, and [Fe(CN)₆]^4? in methanol and other non-aqueous solvents exhibit new, broad absorptions in the visible spectral range because of second-sphere interactions due to ion pair charge-transfer (IPCT). With the decreasing of the acceptor ability of the solvent and decreasing oxidation potential of the complex anion the absorptions are red-shifted. Substituents at the diphenyliodonium ion do not influence the absorption maxima. Irradiation into the IPCT bands leads to an efficient long-wavelength photooxidation of cyanometallate in competition with the photoinduced catalytic destruction of diphenyliodonium /ions.     

Synthesis,crystal structure and non-linear optical properties of a new cyanide-containing compound

Reaction of K₃[Fe(CN)₆], NiCl₂ and diethylenetriamine (dien) resulted in the formation of a cyanide-containing heterometallic compound [Ni(dien)₂]₂[Fe(CN)₆]·4H₂O 1. The structure consists of two octahedral [Ni(dien)₂]²⁺ cations, one octahedral [Fe(CN)₆]^4? anion and four crystallization water molecules, which are held together by hydrogen-bonding interactions. Its TG curve exhibits two stages of mass loss. Compound 1 in DMF solutions has a very strong third-order non-linear optical (NLO) behavior with an absorption coefficient and refractive index α₂?=?1.10?×?10^?11?m?w^?1, n ₂?=??3.05?×?10^?19?m²?w^?1, respectively, and third-order NLO susceptibility χ⁽³⁾ 4.34?×?10^?13?esu.     

Cyano-bridged Heterotrinuclear Molybdenum(IV)-Nickel(II) Complexes: Synthesis,Crystal Structure and Magnetic Properties

Two novel cyano-bridged heterotrinuclear molybdenum(IV)-nickel(II) complexes ([Ni(en)₂(H₂O)]_2-[Mo(CN)₈]·2H₂O, 1, and [NiL(H₂O)]₂[Mo(CN)₈]·4H₂O, 2), where en=1,2-diaminoethane and L= 1,3,6,9, 11,14-hexaazacyclo[12,2,1,1^6,9]octodecanne were synthesized and characterized. The crystal structure of 1 was determined. The structure consists of trinuclear units, space group C2/c, with unit cell dimensions a=17.178(9), b=11.032(5), c=17.629(8) Å, α=108.484(8)°. The temperature dependence of the magnetic susceptibilities for 1 and 2 was analyzed by means of a Hamiltonian expression leading to J=-0.87cm^-1, ZJ'=0.65cm^-1, D=0.02cm^-1, g _Ni=2.45 for complex 1, and J=-0.87cm^-1, ZJ'=0.56cm^-1, D=0.02cm^-1, g, _Ni=2.45 for complex 2.     

Kinetics of the oxidation of octacyanomolybdate(IV) by periodate in aqueous acid

Summary The kinetics of oxidation of [Mo(CN)₈]^4– by IO ₄ ^– in aqueous acid is described by the equation: d[{Mo(CN)₈}^3–]/ dt=2k₃[{Mo(CN)₈}^4–][IO ₄ ^– ][H⁺]. Unlike IO ₄ ^– oxidations of [Fe(CN)₆]^4– and [W(CN)₈]^4–, no [H⁺] independent term exists in the [Mo(CN)₈]^4– reaction, which indicates that, in neutral and alkaline solutions, oxidation of [Mo(CN)₈]^4– is thermodynamically unfavourable. An inner-sphere mechanism, consistent with the rate law, is proposed. This conclusion is based, in the absence of direct evidence, on the observed behaviour of IO ₄ ^– as an inner-sphere oxidant.     

A ladder-like 4d–4f complex constructed from edge-sharing rhombus and square of Mo2Yb2 based on [Mo(CN)8]4? and Yb3+ ions as building Blocks

A novel 4d-4f complex, {Cs[Yb(MeOH)₃(DMF)(H₂O)Mo(CN)₈] · H₂O} _n (1) (DMF = N,N′-dimethylformamide) has been synthesized and structurally characterized. The complex 1 is a one-dimensional (1D) infinite chain, which adopts a 1D ladder-like structure motif assembled from an edge-sharing rhombus and square of Mo₂Yb₂ based on the [Mo(CN)₈]⁴⁻ and Yb³⁺ as building blocks. The complex 1 crystallizes in triclinic, space group P1 with a = 9.841(2) b = 10.226(2) ?, c = 13.404(3) ?, α = 82.02(3)°, β = 86.86(3)°, γ = 65.10(3)°, V = 1211.7(4) ?³ and Z = 2.     

Cyano-bridged heterometallic complexes directed by binuclear copper units

A tridentate N,O-donor, 1,3-bis(3,5-dimethylpyrazol-1-yl)propan-2-ol (HL), has been employed to synthesize cyano-bridged complexes and six heterometallic complexes with [Cu₂L₂] or [Cu₂L₂(H₂O)] have been generated by using slow diffusion. With slightly different synthetic conditions, subtle variations in the crystal structures of the complexes occur. [Cu₂L₂][Fe(CN)₅NO]?2CH₃CN (1) and [Cu₂L₂][Fe(CN)₅NO]?H₂O (2), synthesized in different solvents with the same precursor, exhibit a very similar 1-D zig-zag chain motif in different space groups, P2₁ and P-1, respectively. Similarly, [Cu₂L₂(H₂O)][Ni(CN)₄]·H₂O (3) and [Cu₂L₂][Ni(CN)₄]?H₂O (4), synthesized with different diffusion methods, feature trinuclear and 1-D zig-zag chain structures, which indicates a solvent effect of water. [Cu₂L₂(H₂O)]₂[Cu₂L₂][W(CN)₈]₂·8H₂O (5) is composed of two [W(CN)₈]^3? and three [Cu₂L₂]²⁺ units. In the octanuclear structure, [W(CN)₈]^3? and one [Cu₂L₂]²⁺ bridge and the other two [Cu₂L₂]²⁺ are terminal to stop extending the 1-D structure. [CuL][Ag_2.24Cu_0.76(CN)₄] (6) exhibits a discrete structure, in which the complex anion forms a unique 2-D 6³ network and the complex cations are inserted in the space between two adjacent networks. Magnetic properties of 1 and 4 are discussed.     

Cyano-complexes and salts with tetracyanonickellateII and N,N-bis(2-hydroxyethyl)-ethylenediamine: synthesis,IR spectra,magnetic properties,thermal analyses,and crystal structures

Four cyano complexes, [Ni(N-bishydeten)Ni(CN)₄] _n (c1), [Cu(N-bishydeten)₂][Ni(CN)₄] (c2), [Zn₂(N-bishydeten)₂Ni(CN)₄] _n (c3), and [Cd(N-bishydeten)₂][Ni(CN)₄] (c4), have been synthesized and characterized by FT-IR, elemental, and thermal analyses. The structures of c2 and c4 were determined by single-crystal X-ray diffraction studies; both structures contain isolated cations and anions. The c2 consists of [Cu(N-bishydeten)₂]²⁺ with octahedrally coordinated Cu^II and diamagnetic [Ni(CN)₄]^2–, but c4 consists of [Cd(N-bishydeten)₂]²⁺, in which Cd^II is eight coordinate with two tetradentate N-bishydeten and diamagnetic [Ni(CN)₄]^2–. The value of the shape measure S (^o) indicates that the coordination geometry around Cd^II lies along D _2d [dodecahedron; (dd)], C _2v [bicapped trigonal prism; (btp)], and D _4d [square antiprism; (sap)] but close to D _2d and D _4d. Variable temperature magnetic susceptibility measurements of c1 and c2 show the presence of little antiferromagnetic interaction below 20?K. Thermal analyses reveal that first neutral N-bishydeten and then cyano ligands were liberated from the complexes.     

Stepwise Assembly of MII7 Clusters Revealed by Mass Spectrometry,EXAFS, and Crystallography

The square‐planar monomer NiL₂ ( Ni₁ ), L=2‐ethoxy‐6‐(N‐methyl‐iminomethyl)phenolate, reacts with M(H₂O)₆(ClO₄)₂, M=Ni or Co, to form heptanuclear disks [Co_xNi_7?x(OH)₆(L)₆](ClO₄)₂ ? 2 CH₃CN ( Co _x Ni_7?x , x=0–7) and the co‐crystal [Co_xNi_7?x(OH)₆L₆][NiL₂](ClO₄)₂ ? 2 CH₃CN ( Co _x Ni_7?x ‐Ni₁ ) under ambient conditions. It has proved possible to explore the bottom‐up assembly process of Co _x Ni_7?x and Co _x Ni_7?x ‐Ni₁ in real time. The final products have been characterized by thermogravimetric analysis, IR, elemental analysis, ICP‐MS, and single‐crystal X‐ray diffraction. Time‐dependent mass spectrometry (MS) revealed the following reaction steps: Ni₁→[M₂L₃]⁺→[M₄(OH)₂L₄]²⁺→[M₇(OH)₆L₆]²⁺. In contrast, the reaction of Ni₁ with Zn²⁺ only reaches halfway, and crystallographic evidence indicates a butterfly structure for [Zn₂Ni₂(OH)₂Cl₂] ( Zn₂Ni₂ ), an intermediate that is difficult to isolate in the above Ni‐Co series. A summation method has been used to analyze the MS of bimetallic clusters with very similar atomic masses, as is the case for Co and Ni. The results provide ample information on the distribution of Co and Ni within each cluster and their statistical distribution within selected crystals.