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1.
Four bis(N-adamantyldithiocarbamato)metal(II) complexes [M(S2CNHC10H15)2] (M = Ni, Zn, Cd, and Hg) were prepared by metathesis of the corresponding potassium salt, K[S2CNHC10H15]. Characterization of the prepared complexes shown that the presence of only one band in the region 1000 cm−1 in IR spectra can be attributed to a completely symmetrical bonding of the dithiocarbamate ligand, acting in a symmetrical bidentate mode. Also the short thioureide C-N distance in X-ray analysis of Ni complex confirm the delocalization of the π electrons over the S2CN moiety and strong double bond character.  相似文献   

2.
Two closely related 1:1 salts are obtained upon electrocrystallization of BEDT-TTF (BEDT-TTF: bis(ethylenedithio)tetrathiafulvalene) in the presence of the isosteric [M(tfadt)2] dithiolene complexes (tfadt: 1-trifluoromethyl-2-cyano-1,2-dithiolato), which essentially differ by their spin state, S = 0 in [Au(tfadt)2], S = 1/2 in [Ni(tfadt)2]. In both [BEDT-TTF][M(tfadt)2] salts, the BEDT-TTF radical cations form chains with a strong lateral overlap and strong antiferromagnetic interactions while the paramagnetic anions in the nickel-containing salt [BEDT-TTF][Ni(tfadt)2] are essentially non-interacting. The structural differences between the nickel and gold complexes are analyzed and discussed.  相似文献   

3.
Double complex salts [M(NH3)4][M′(Ox)2(H2O)2] · 2H2O (M = Pd, Pt, M′ = Ni, Zn) were synthesized by combination of solutions containing corresponding cations [M(NH3)4]2+ and anions [M′(Ox)2(H2O)2]2−. The salts obtained were characterized by IR spectroscopy, thermal analysis, powder and single crystal X-ray diffraction. The prepared compounds are isostructural and crystallize in the orthorhombic crystal system (space group I222, Z = 2). Thermal decomposition of the salts in helium or hydrogen atmosphere at 200-400 °C results in formation of nano-sized bimetallic powders. Depending on the phase diagram of the respective bimetallic system and temperature conditions, they can be single phase or multiphase products. In particular, thermal decomposition of double complex salts [M(NH3)4][Zn(Ox)2(H2O)2] · 2H2O (M = Pd, Pt) results in formation of PdZn and PtZn intermetallic compounds, correspondingly. Decomposition of [Pd(NH3)4][Ni(Ox)2(H2O)2] · 2H2O affords a disordered solid solution Pd0.5Ni0.5. Disordered Pt0.5Ni0.5 was obtained from [Pt(NH3)4][Ni(Ox)2(H2O)2] · 2H2O in helium atmosphere, while in hydrogen atmosphere - a two-phase mixture of disordered Pt0.5Ni0.5 and ordered PtNi. In all cases crystallite sizes of bimetallic particles varied within 50-250 Å.  相似文献   

4.
Salts of [FeIII(sal2-trien)]+and [FeII(phen)3]2+ cations and M[(dcbdt)2] anions with M = Ni and Au (dcbdt = dicyanobenzenedithiolate) with formula [Fe(sal2-trien)] [M(dcbdt)2] and [Fe(phen)3] [M(dcbdt)2]2 were obtained and characterized by single X-ray diffraction and magnetic measurements. None of these salts shows a clear spin crossover behaviour and their magnetic properties are due essentially to the cations in a high spin S = 5/2 and low spin states for the FeIII and FeII salts respectively. The magnetic Ni sublattices in both compounds appear to have a negligible direct contribution to the magnetization but enhance the AF interactions in the cation sublattice.  相似文献   

5.
Selective substitution of the chlorine atom coordinated to cobalt in the paramagnetic Mo3(CoCl)S4(dmpe)3Cl3 (dmpe = 1,2-bis(dimethylphosphanyl) ethane) complex with a S = 1/2 ground state has been achieved by iodine oxidation to afford the also paramagnetic [Mo3(CoI)S4(dmpe)3Cl3]I ([1]I) salt with a S = 1 ground state in almost quantitative yield. Replacement of chorine by iodine has no significant effect on the structural and electrochemical properties of the Mo3CoS4 system. Metathesis of the [1]I salt with the paramagnetic nickel anionic dithiolate [Ni(mnt)2] (mnt = maleonitrilodithiolate) affords [1]2[Ni(mnt)2]. The stoichiometry evidenced by X-ray analysis reveals that reduction of the [Ni(mnt)2] radical to the corresponding diamagnetic closed shell [Ni(mnt)2]2− dianion, presumably via dismutation, has occurred during the metathesis process. The crystal structure of [1]2[Ni(mnt)2] consists of [Ni(mnt)2]2− dianions sandwiched by two cluster 1+ cations which yield {1+·[Ni(mnt)2]2−·1+} subunits arranged along the crystallographic c axis. Magnetic susceptibility measurements for [1]2[Ni(mnt)2] show a χT product of 0.99 emu K/mol largely unchanged in the 10-300 K range. This behavior agrees with the presence of an S = 1 cluster 1+ cation while the Ni(mnt)2 moiety does not contribute to the paramagnetism of the sample.  相似文献   

6.
Combined pH-metric, UV-Vis, 1H NMR and EPR spectral investigations on the complex formation of M(II) ions (M=Co, Ni, Cu and Zn) with N-(2-benzimidazolyl)methyliminodiacetic acid (H2bzimida, hereafter H2L) in aqueous solution at a fixed ionic strength, I=10−1 mol dm−3, at 25 ± 1 °C indicate the formation of M(L), M(H−1L) and M2(H−1L)+ complexes. Proton-ligand and metal-ligand constants and the complex formation equilibria have been elucidated. Solid complexes, [M(L)(H2O)2] · nH2O (n=1 for M = Co and Zn, n=2 for M = Ni) and {Cu (μ-L) · 4H2O}n, have been isolated and characterized by elemental analysis, spectral, conductance and magnetic measurements and thermal studies. Structures of [Ni(L)(H2O)2] · 2H2O and {Cu(μ-L) · 4H2O}n have been determined by single crystal X-ray diffraction. The nickel(II) complex exists in a distorted octahedral environment in which the metal ion is coordinated by the two carboxylate O atoms, the amino-N atom of the iminodiacetate moiety and the pyridine type N-atom of the benzimidazole moiety. Two aqua O atoms function as fifth and sixth donor atoms. The copper(II) complex is made up of interpenetrating polymeric chains of antiferromagnetically coupled Cu(II) ions linked by carboxylato bridges in syn-anti (apical-equatorial) bonding mode and stabilized via interchain hydrogen bonds and π-π stacking interactions.  相似文献   

7.
New and improved procedures are reported for the synthesis of [M(DBCOT)(μ-Cl)]2 (M = Rh, Ir; DBCOT = dibenzo[a,e]cyclooctatetraene) from MCl3(H2O)x or [M(COD)(μ-Cl)]2 and DBCOT. Treatment of [M(DBCOT)(μ-Cl)]2 with [(LAu)3(μ-O)]BF4(L = PPh3, PtBu3) yields the mixed-metal oxo complexes [M(DBCOT)(μ4-O)(AuL)2]2(BF4)2. Dimeric [Rh(DBCOT)(μ-OH)]2 is obtained from the reaction of [M(DBCOT)(μ-Cl)]2 with KOH in EtOH/H2O. All complexes except [Rh(DBCOT)(μ-Cl)]2 have been structurally characterized by single crystal X-ray diffraction.  相似文献   

8.
A new series of complexes of cobalt(II) fluoride, nickel(II) fluoride, copper(II) fluoride and zinc(II) fluoride with imidazole were synthesized and characterized by elemental analysis, molar conductance, magnetic moments, IR and electronic absorption measurements. Based on elemental and spectral data, the complexes were found to be of [M(im)6]F2 · XH2O type, where M is Co(II), Ni(II), Cu(II) and Zn(II) and X 4-5. The magnetic moments and spectral data suggested that all the complexes possessed an octahedral geometry. The crystal structure of the nickel complex, [Ni(im)6]F2 · 5H2O, is also reported in which nickel atom is surrounded by six nitrogen atoms of imidazole. Strong intra- and inter-molecular hydrogen bonding exists between fluoride ions (uncoordinated), nitrogen of imidazole and the -OH of water molecules.  相似文献   

9.
The reaction of [Ni(tmhd)2] and [Ni(dbm)2] with N-donor chelating ligands in dichloromethane and acetone, respectively, yields the complexes [Ni(tmhd)2(L-L)] (L-L = 2,2′-bpy 1, phen 2 and dmae 3) and [Ni(dbm)2(L-L)] (L-L = 2,2′-bpy 4, phen 5, dmae 6). UV-Vis spectroscopy shows very strong bands in the UV region consistent with ligand centred π → π transitions. The electrochemical studies of 1-6 reveal oxidation to Ni(III). The [Ni(tmhd)2(L-L)] 1-3 are more easily oxidized by ca. 300 mV and are quasi-reversible whereas for the [Ni(dbm)2(L-L)] series only complex 6 shows significant reversibility. X-ray crystallographic studies have been conducted in the case of [Ni(dbm)2(phen)] 5 and [Ni(dbm)2(dmae)] 6. The structures both show that the nickel metal centre is octahedral with an O4N2 coordination environment. In the structures the β-diketonate ligands exhibit a cis-arrangement, with the metal displaced out of the planar chelate ring.  相似文献   

10.
Hydrothermal synthesis has afforded a family of three structurally related metal phthalate (pht) 1-D coordination polymers incorporating the kinked dipodal organodiimine 4,4′-dipyridylamine (dpa), with a general formulation of [L2M(dpa)2M(H2O)4] · H2O (L = pht, M = Co, 1, M = Ni, 2; L = 4-methylphthalate (4-mpht), M = Co, 3). Single crystal X-ray diffraction of 1 and 2 revealed the presence of one-dimensional (1-D) polymeric chains consisting of [M(H2O)4]2+ and [M(pht)2]2− subunits linked through dpa tethers. These chains in turn conjoin into pseudo 2-D layers and 3-D networks via extensive supramolecular hydrogen bonding pathways. An extremely similar structure is observed for 3 despite the presence of the bulkier methyl group substituent. 1-3 were further characterized via infrared spectroscopy and elemental and thermogravimetric analysis. 1-3 represent the first dicarboxylate coordination polymers incorporating dpa tethering ligands.  相似文献   

11.
Two new nickel(II) complexes of the composition [Ni(cyclam)(Hdipic)2] · 2H2O (1) and [Ni(cyclam)(H2O)2][Ni(dipic)2] · 2.5H2O (2) (cyclam = 1,4,8,11-tetraazacyclotetradecane) have been prepared and structurally characterized by a combination of analytical, spectroscopic, thermogravimetric, and crystallographic methods. The structure of 1 shows that the central nickel(II) ion is coordinated axially by two monodentate Hdipic ligands. The discrete neutral complex 1 further extends its structure by hydrogen bonding interactions to form a one-dimensional supramolecule. The structure of 2 consists of two independent nickel(II) centers. Water molecules instead of dipic ligands prefer to coordinate to the Ni1 ion forming a divalent cation [Ni(cyclam)(H2O)2]2+. Two dipic ligands coordinate to the second Ni2 ion forming a divalent anion [Ni(dipic)2]2−. The divalent cations and anions are charge-balanced, resulting in a molecular salt. The divalent cations and anions are interconnected by multiple types of hydrogen bonding interactions.  相似文献   

12.
The reaction of a solution of sodium 3,5-diphenylpyrazolate, Na[Ph2pz], with Ag(tht)NO3 in dichloromethane affords thin needles of unsolvated and light-stable dimer of trimers [Ag3(μ-3,5-Ph2pz)3]2. The complex is characterized by X-ray crystallography and elemental analysis. The two trimers are rotated anti to each other. Three silver atoms bridged through exobidentate pyrazolate groups form a slightly puckered nine-membered ring with the shortest Ag?Ag intramolecular interaction in the metallocycle of 3.3571(8) Å. The other two silver centers are weakly interacting, Ag(3)?Ag(1) = 3.49 Å and Ag(3)?Ag(2) = 3.52 Å. The intermolecular interaction between the two trimers is Ag?Ag = 2.9712(14) Å. Packing diagram shows the dimer of trimer units are independent. Density Functional Theory calculations show that the M?M interaction is due to dispersion forces. [Ag3(μ-3,5-Ph2pz)3]2 crystallizes in the monoclinic space group C2/c with a = 22.169(4), b = 15.269(3), c = 22.482(5) Å, β = 103.69(3)° and V = 7394(3) Å3.  相似文献   

13.
The reaction of M(NO3)2·xH2O (M = Cu, Ni and Co; x = 3 for Cu and x = 6 for Co/Ni), imidazole (Im) and sodium dicyanamide (dca) afforded the complexes [M(Im)2(dca)2] (where M = Cu for 1, M = Ni for 2, and M = Co for 3). All of them have been characterized structurally by single crystal X-ray diffraction measurements. X-ray analysis reveals that the dicyanamido ligand features the μ1,3 bridging mode that led to the formation of two-dimensional structure of complex 1 while complexes 2 and 3 attribute an infinite one-dimensional chain like structure to generate the fascinating molecular assemblies. The {N(CN)2} ligands present in the complexes 2 and 3 are coordinated in end-to-end (μ1,5) fashion. All the complexes have distorted octahedral geometry around the central metal ion and coordinated by two amine nitrogen atoms from imidazole ligands and four nitrogen atoms from dca ligands. The variable temperature (2-300 K) magnetic susceptibility measurements showed that the magnetic interaction between the metal centers in the complex 1 is dominantly ferromagnetic while the metal ions in complex 3 are antiferromagnetically coupled. On the contrary, complex 2 is a simple paramagnet. The results of magnetic model are in good agreement with the experimental data.  相似文献   

14.
In the aerobic oxidation of methanol catalyzed by a Ni(II)(TRISOX) complex [H3TRISOX = tris(1-propan-2-onyl oxime)amine], an intermediate is observed spectroscopically. The intensities of both the UV-Vis absorption and electron paramagnetic resonance (EPR) spectra associated with this intermediate maximize during the time period of maximum formaldehyde production, and decrease as the methanol oxidation activity decreases. The UV-Vis spectrum has prominent features at 350, 420, and 535 nm. The EPR spectrum is centered at g = 2.00 and shows splittings of 28 ± 5 G. Both of these spectra are consistent with characterization of the intermediate as including one or more iminoxyl radicals derived from the oximate groups of the TRISOX ligand. Spectroscopic features very similar to those in the air-oxidized intermediate are observed in electrochemically oxidized samples, suggesting that the electrochemically generated complex will be a useful model for the intermediate observed during catalytic turnover. The crystal structure of a Ni(II) complex with an intermediate protonation state of the ligand, [Ni(II)2(H2TRISOX)221-ONO2)](NO3) · (CH3CN) · 5(H2O), 4, has been structurally characterized. Comparison to the previously reported [Ni(II)(H2TRISOX)(CH3CN)]2(ClO4)2, 3, shows that bis(μ-oximate) dimers can form either with or without an additional bridging ligand. Addition of the nitrato bridge decreases the Ni-Ni distance from 3.5752(13) Å in 3 to 3.2014(4) Å in 4. It is intriguing to note that the reactions catalyzed by the Ni(II)(TRISOX) complex, the net transfer of two hydrogen atoms from an alcohol or amine substrate to O2, are the same reactions catalyzed by several different metalloenzymes that also incorporate both a redox active metal and a redox active organic component in their active sites.  相似文献   

15.
The sterically hindered tetrakis-(3-(p-tolylpyrazolyl)borate [pz0Tpp-Tol] has been prepared and its reaction with CuX2.nH2O (X = Cl or acetate (OAc), M(NO3)2.6H2O (M = Ni, or Co) and MCl2 (M = Zn or Cd) has been investigated. [M(pz0Tpp-Tol)X(Hpzp-Tol)] (M = Cu, X = Cl or OAc; M = Ni or Co, X = NO3) and [M(pz0Tpp-Tol)Cl(Hpzp-Tol)2-n(H2O)n] have been synthesised and their spectroscopic properties described, the five-coordinated Cu species being also structurally characterized. The methyl groups in the para-tolyl fragments of the ligand strongly influences the stoichiometry and structure of the metal complexes.  相似文献   

16.
We report here the crystal and molecular structures of three compounds [FeL2] [Ni(mnt)2] (1), [FeL2]2 [Ni(mnt)2]3·2H2O (2) and [FeL2] [Cu(mnt)2]·2CH3CN (3) where L = 2,6-bis(3,5-dimethylpyrazol-1-ylmethyl)pyridine and mnt = maleonitriledithiolate, and their detailed spectroscopic and magnetic properties using variable temperature Mössbauer, EPR, susceptibility studies, along with room temperature electron spectroscopy for chemical analysis (ESCA) studies. The observed temperature dependant high spin/low spin (HS/LS) ratios of [FeL2]2+ cations in these lattices, exhibiting ‘reverse spin cross-over’ measured unequivocally by Mössbauer, have been interpreted as resulting from differing amount of ‘void space’ in the lattice, a measure of the ease of lattice dynamics originating from ligand L. Differential scanning calorimetric data points this HS/LS transition to order-disorder type of second order phase transitions. While trying to test this lattice dynamics controlled property of [FeL2]2+ cations an unusual behavior of cocrystallization of two planar complex anions of the same type in two different oxidation states, viz. [Ni(mnt)2]2− and [Ni(mnt)2], was observed in [FeL2]2 [Ni(mnt2)]3, supported by crystallography, ESCA chemical shifts of Ni 2p3/2 and EPR. The susceptibility data in combination with ESCA chemical shifts of S 2p3/2 and Ni 2p3/2 on all the compounds reveal the importance of charge transfer between the two counter ions.  相似文献   

17.
Four saccharinate complexes of divalent transition metals with 2,2′:6,2″-terpyridine (terpy) as a co-ligand have been synthesised, and characterised by elemental analysis and single crystal X-ray diffraction at low temperature. The complexes [M(terpy)(sac)(H2O)2] sac · H2O (1, M = Mn; 2, M = Co; 3, M = Ni) are isostructural, crystallising in space group Pbca. The metal ions have approximately octahedral coordination, with the two coordinated water molecules occupying cis-positions. These water molecules are hydrogen-bonded to the oxygen atom in the free water molecule. The copper(II) ion in the anhydrous complex [Cu(terpy)(sac)2] 4 is five-coordinate; the compound crystallises in the space group P2(1)/c.  相似文献   

18.
Hydrothermal synthesis has afforded a family of four coordination polymers containing divalent nickel or cobalt and pendant-arm pyridylcarboxylate ligands. Utilizing 3-pyridylacetic acid and appropriate metal precursors produced [M(3-pyrac)2(H2O)2] phases (M = Co (1); M = Ni (2)), while 3-pyridylpropionic acid generated [M(3-pyrprop)2(H2O)2] coordination polymers (M = Co (3); M = Ni (4)). Single crystal X-ray diffraction revealed that 1-4 all display discrete 2-D layers with (4,4)-topology, anchored via bridging 3-pyridylcarboxylate ligands bearing monodentate carboxylate termini. Intralamellar hydrogen bonding between the aquo ligands and unligated carboxylate oxygen atoms is observed within 1-4. The pseudo 3-D structures of 1-4 are further assembled via stacking of individual neutral layers by interlayer hydrogen bonding. Thermal properties are also discussed.  相似文献   

19.
The crystal structures of the C-H?O hydrogen-bonded, 1:1 complex salts of with [Ni(dmit)2] 2MMP, 3MMP and 4MMP (ortho-, meta-, and para-methoxycarbonyl N-methyl-pyridinium, respectively) cations with have been investigated. All complex salts formed non-segregated stacks with the anions being sandwiched between layers or dimers of cations. Within these salts, the arrangement of the counter cations are structurally modulated by two weak intermolecular hydrogen bonds between the hydrogen of the pyridinium ring, methyl group or one of the two and the CO group of the cations. The alignment of Ni(dmit)2 molecules is found to be mainly governed by the attached position of methoxycarbonyl group. Powders of (2MMP)[Ni(dmit)2], (3MMP)[Ni(dmit)2] and (4MMP)[Ni(dmit)2] salts exhibited room temperature conductivities of 4.33 × 10−10, 1.80 × 10−6 and 5.60 × 10−6 S cm−1, respectively.  相似文献   

20.
A new compound of formula [Fe(qsal)2][Ni(dmit)2] (1) has been synthesised, structurally and magnetically characterised (qsalH = N-(8-quinolyl)salicylaldimine, dmit2− = 1,3-dithiol-2-thione-4,5-dithiolato). Its structural features and its magnetic behaviour were compared with those of [Fe(qsal)2]-based complexes, and more particularly [Fe(qsal)2][Ni(dmit)2] · 2CH3CN.  相似文献   

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