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Selenium and sulfur derivatives of lead(ii) acylchalcogourato complexes have been used to deposit PbSxSe1−x thin films by AACVD. By variation of the mole ratio of sulfur and selenium precursors in the aerosol feed solution the full range of compositions of PbSxSe1−x was obtained, i.e. 0 ≥x≥ 1. The films showed no contaminant phases demonstrating the potential for acylchalcogourato metal complexes as precursors for metal chalcogenide thin films. The crystal structure for bis[N,N-diethyl-N′-2-naphthoylthioureato]lead(ii) was solved and displayed the expected decreases in Pb–E bond lengths from the previously reported selenium variant. [ABSTRACT FROM AUTHOR]

The reaction between 3,6,9-trithia-1(2,6)-pyridinacyclodecaphane and representative group 10 and 11 metal salts [Cu(NO3)2, NiCl2 or Ag(CF3CO2)] afforded 1:1 complexes, which in the case of CuII and AgI were characterised by single-crystal X-ray crystallography. The catalytic activity of these complexes in A³-coupling reactions between aldehydes, terminal alkynes and amines was assessed in both protic (water) and aprotic (toluene) media. These A3-reactions prove to be more efficient, proceed with lower catalyst loadings and with faster reaction rates, when conducted in a focused microwave reactor as compared to the same reactions promoted by standard, thermal, modes of activation. [ABSTRACT FROM AUTHOR]

A mixed ligand complex of Cu(II) with 1,10-phenanthroline and succinate has been synthesized from the reaction of hydrated copper nitrate, succinate, and 1,10-phenanthroline. The nature of bonding and the structure of the complex were characterized by elemental analyses, infrared spectrum, TGA/DTA, and X-ray diffraction. The crystal crystallizes in triclinic space group P 1. The complex is polymeric and the geometry around each copper varies from square planar to distorted square pyramidal or octahedral. Each copper coordinates two oxygens of succinate and two nitrogens of 1,10-phenanthroline. The thermal decomposition of the complex has also been studied by TGA and DTA under inert atmosphere. [ABSTRACT FROM AUTHOR]

A series of new metal complexes of thiobiurets and dithiobiurets have been synthesized and characterized. The compounds are potentially useful as novel single source precursors for the deposition of metal sulfide thin films or nanoparticles. [ABSTRACT FROM AUTHOR]

Two heterometallic polynuclear complexes, [Cd2(OAc)6(μ-O)Cu4(dmae)4]·H2O (1) and its zinc analogue [Zn2(OAc)6(μ-O)Cu4(dmae)4]·3H2O (2), were synthesized by simple chemical techniques. These complexes were characterized by their melting point, elemental analysis, FT-IR, APCI-MS and single crystal X-ray diffraction. The complexes consist of a common Cu4moiety and a Cd2or Zn2moiety in 1and 2with the space groups C2/cand P1, respectively. Thermogravimetric studies prove that they can be easily thermally decomposed and can be used as precursors in aerosol-assisted chemical vapor deposition (AACVD) to yield ceramic composites that might have applications in industry and new technologies. Thin ceramic films thus deposited have good adhesion to the substrate and were characterized by SEM, EDX and powder X-ray diffractometry. SEM micrographs show morphologically evenly distributed phases that were identified by PXRD to be Cu–CdO in the case of 1and Cu–ZnO for 2. [ABSTRACT FROM AUTHOR]

A facile method for the preparation of dimorpholides of dithioacetylacetonate is described together with a X-ray single crystal structure of the ligand and of [Cd(msacmsac)2(NO3)2] (msacmsac = dimorpholinodithioacetylacetonate). The cadmium complex has been used as a single source precursor for the deposition of the CdS thin films by the aerosol assisted chemical vapour deposition (AACVD) method or as nanorods by thermolysis in oleylamine. The thin films and nanorods were characterized by electronic spectra (UV-Vis), photoluminescence (PL), X-ray diffraction (XRD), selected area electron diffraction (SAED), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). To the best of our knowledge [Cd(msacmsac)2(NO3)2] is the first complex in its class to be used as a single source precursor to deposit CdS thin films or nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract: The alkynyl complexes [Mo(C CR)(R′-dab)(η-C7H7)] (dab = diazabutadiene; R′ = t Bu, R = Ph, 2a; C6H4–4-Me, 3a; t Bu, 4a; R′ = C6H4–4-Me, R = Ph, 2b) have been synthesised by reaction of [MoBr(R′-dab)(η-C7H7)] with LiC CR in thf. Crystallographic characterisation of [Mo(C CC6H4–4-Me)( t Bu-dab)(η-C7H7)], 3a determines a Mo-Cα bond distance of 2.154(3) Å. Cyclic voltammetric investigations on the alkynyl complexes 2a, 2b, 3a, 4a and the extended chain butadiynyl derivative [Mo(C CC CSiMe3)( t Bu-dab)(η-C7H7)], 5a, reveal that each complex exhibits a chemically and electrochemically reversible one-electron oxidation to give the corresponding 17-electron radical cation. Characterisation of the radicals [2a]+, [2b]+, [3a]+, and [5a]+ by IR and EPR spectroscopic techniques indicates that the redox process is strongly metal centred. Spectroscopic and synthetic investigations establish that 17-electron radicals of the type [Mo{(C C) n C CR)}(R′-dab)(η-C7H7)]+ (n = 0 or 1) have relatively low thermodynamic stability. [Copyright &y& Elsevier]

The reaction of [MoBr(dppe)(η-C 7 H 7 )] (dppe = Ph 2 PCH 2 CH 2 PPh 2 ) with HC CC CSiMe 3 and Na[BPh 4 ] in 1:1 NHEt 2 /THF as solvent yields the aminoallenylidene complex [Mo{C C C(Me)NEt 2 }(dppe)(η-C 7 H 7 )][BPh 4 ], [ 1 ][BPh 4 ]. The reaction likely proceeds via nucleophilic addition of NHEt 2 at C γ of a butatrienylidene intermediate. Structural and spectroscopic characterisation of [ 1 ][BPh 4 ] indicate a significant contribution of an iminium alkynyl resonance form to the overall structure of the heteroatom stabilised allenylidene ligand. The X-ray structural study of [ 1 ][BPh 4 ] determines a Mo C α bond length of 2.077(3) Å, intermediate between that of the cumulenic diphenylallenylidene analogue [Mo(C C CPh 2 )(dppe)(η-C 7 H 7 )][PF 6 ] (1.994(3) Å) and the alkynyl compound [Mo(C CPh)(dppe)(η-C 7 H 7 )] (2.138(5) Å). Complex [ 1 ][BPh 4 ] undergoes a reversible one-electron oxidation with E ½ = −0.19 V with respect to the FeCp 2 /FeCp 2 + couple and the stable 17-electron radical dication [ 1 ] 2+ is readily observed by spectroelectrochemical methods. IR spectroelectrochemistry in CH 2 Cl 2 demonstrates that the ν (CCC) stretch, characteristic of the allenylidene ligand, shifts to higher wavenumber (from 1959 to 2032 cm −1 ) as a result of oxidation of [ 1 ] + to [ 1 ] 2+ , consistent with a strongly metal-centred redox process and an enhancement in the alkynyl character of the allenylidene ligand following one-electron oxidation. [ABSTRACT FROM AUTHOR]

The reaction of [FeI(dppe)Cp], 1 (dppe Ph 2 PCH 2 CH 2 PPh 2 ) with HC≡CSiMe 3 in refluxing methanol results in formation of a mixture of the vinylidene complex [Fe( C CH 2 )(dppe)Cp] + , 2 and the heteroatom stabilised alkoxycarbene [Fe{C(OMe)Me}(dppe)Cp] + , 3 . The carbene 3 is formed by addition of the alcohol solvent to the reaction intermediate vinylidene 2 , and prolonged reflux in methanol (4 days) resulted in complete conversion of 2 to 3 . The methoxycarbene, 3 was isolated as a stable solid and fully characterised by spectroscopic and structural methods. Vinylidene 2 also reacts with ethanol to give the ethoxycarbene [Fe{C(OEt)Me}(dppe)Cp] + , 4 but no reaction was observed in refluxing isopropanol, thus providing a specific synthesis of vinylidene 2 from 1 and HC≡CSiMe 3 . An example of an alcohol based, intramolecular nucleophilic addition to a mono-substituted vinylidene [Fe( C CHR)(dppe)Cp] + was uncovered in the reaction of 1 with 3-butyn-1-ol which leads to the synthesis of the cyclic oxacarbene complex [Fe{C(CH 2 ) 3 O}(dppe)Cp][PF 6 ], 5 . X-ray crystallographic investigations on 3 [I] and 5 [PF 6 ] determine Fe-C α bonds lengths of 1.851(5) and 1.834(2) Å respectively, intermediate between previously reported Fe-C α distances for the amino carbene [Fe{C(NH 2 )Me}(dppe)Cp][PF 6 ] and the alkylidene complex [Fe{ C(H)Me}(dppe)Cp*][PF 6 ]. [ABSTRACT FROM AUTHOR]

Cadmium dithiocarbamato complexes of piperidine ( 1 ) and tetrahydroquinoline ( 2 ) were synthesized and characterized by elemental analysis, FT-IR spectroscopy, NMR and TGA analyses. The X-ray single crystal structure of bis (piperidinedithiocarbamato)cadmium(II) complex ( 1 ) was determined. The synthesized compounds were used as single source precursors to deposit CdS films on glass substrates at 350, 400 and 450 °C using the aerosol assisted chemical vapor deposition (AACVD) method. The surface morphology and the size of the CdS films were determined by AFM and SEM analyses; the crystalline phases by p -XRD analyses and the elemental composition by EDX measurements. The particle sizes were found to be in the range between 50–110 nm and 100–220 nm for complex ( 1 ) and ( 2 ), respectively. The electronic properties of the CdS films were analyzed by UV–Vis and Raman spectroscopic methods. Results revealed that the morphology, size and composition of the films are influenced by the deposition temperature. [ABSTRACT FROM AUTHOR]

Lead sulfide has been grown from single molecular precursors within a polymer matrix to form networks of PbS nanocrystals. These materials are model systems for the processing of polymer-nanoparticle layers for flexible hybrid photovoltaic devices. Processing is achieved by spin coating a solution containing the precursor and polymer onto a substrate, followed by heating of the film to decompose the precursor. The effect of precursor chemistry has been explored using lead(II) dithiocarbamates, their 1,10-phen adducts, and lead(II) xanthates with different alkyl chain lengths (butyl, hexyl, and octyl). The xanthates were found to be more promising precursors giving control over nanocrystal size and shape on variation of the alkyl chain length. The lead(II) octyl xanthate complex causes anisotropic growth, forming PbS nanowires within the polymer matrix. [ABSTRACT FROM AUTHOR]

Bis ( O -alkylxanthato)nickel(II) complexes (alkyl=hexyl and octyl) have been synthesised and their X-ray single crystal structures determined. Nickel sulfide thin films were deposited from both complexes at different deposition temperatures by the aerosol assisted chemical vapour deposition (AACVD) method. Phase pure rhombohedral NiS and mixture of rhombohedral NiS (millerites) and Ni 17 S 18 were deposited onto the glass and silicon substrates at temperatures between 250 and 400 °C. SEM images show that the films are based on irregular grains, nanodendrites and feather like morphologies. [ABSTRACT FROM AUTHOR]

Four new complex salts [Ru11Cl(Tpm)(LA)2]- [PF6]n [Tpm = tris(l-pyrazolyl)methane; n - 1, LA = pyridine (py) 1 or ethyl isonicotinate (EIN) 2; n = 3, LA = N-methyl- 4,4'-bipyridinium (MeQ+) 3 or N-phenyl-4,4'-bipyridinium (PhQ+) 4] have been prepared and characterized. Electronic absorption spectra show intense d → μ* metal-to-ligand charge-transfer (MLCT) absorption bands, while cyclic voltammetry reveals a reversible RuIII/II wave, accompanied by quasireversible or irreversible LA based reductions for all except 1. Single crystal X-ray structures have been obtained for l•Me2CO, 2, and 3•Me2CO. For 2--4, molecular first hyperpolarizabilities ß have been measured in acetonitrile solutions via the hyper-Rayleigh scattering (HRS) technique at 800 nm. Stark (electroabsorption) spectroscopic studies on the MLCT bands in frozen butyronitrile allow the indirect estimation of static first hyperpolarizabilities ß0. The various physical data obtained for 3 and 4 are compared with those reported previously for related cis-{Ru11(NH3)4}2+ species [Coe, B. J. et al. J. Am. Chem. Soc. 2005, 127, 4845]. TD-DFT calculations on the complexes in 1--4 confirm that their lowest energy absorption bands are primarily Ru11 --> LA MLCT in character, while Ru11 → Tpm MLCT transitions are predicted at higher energies. DFT agrees with the Stark, but not the HRS measurements, in showing that ß0 increases with the electron-accepting strength of LA. The 2D nature of the chromophores is evidenced by dominant ßxxy tensor components. [ABSTRACT FROM AUTHOR]

Six new PtIIcomplexes of 5-substituted 1,3-bis(N-methylimino)benzene (bIBH)-derived ligands have been synthesizedby direct reactions with K2PtIICl4in glacial acetic acid. The ethenylene groups in the two styryl-substitutedcomplexes undergo E–Zphotoisomerization,as revealed by 1H NMR spectroscopy. The UV–vis spectraof the styryl-/aryl-substituted complexes show intense high-energybands due to ligand-based π → π* transitions anda number of weaker bands at lower energies in the 300–500 nmregion. Time-dependent density functional theory (TD-DFT) calculationsindicate that the latter absorptions have mixed intraligand π→ π* and Pt(d) → π* metal-to-ligand charge-transfer(MLCT) character. Four of the new complexes give vibronically structuredemission profiles in fluid solution at room temperature. The luminescencequantum yields and lifetimes in nondegassed dichloromethane are inthe ranges 0.1–0.2% and 159–170 ns, respectively. Incontrast, the styryl-substituted complexes are nonemissive, due toexcited-state quenching by E→ Zisomerization. DFT indicates that the emissive triplet state hasmixed ligand-to-ligand charge-transfer and MLCT character, with ageometry distorted with respect to the symmetric ground state. Single-crystalX-ray structures have been determined for two of the complexes, showingN–Pt–N angles of ca. 159°. The complex of an unsubstitutedbIB–ligand is deep red and forms columns with shortPt···Pt distances of ca. 3.55 Å, indicating weakintermetallic interactions. [ABSTRACT FROM AUTHOR]

Abstract: A new heterobimetallic, single-source precursor with the formula Ba2(μ-OAc)4(OAc)2Cu4(μ-dmae)4(OH)2 (1) [dmae= N,N-dimethylaminoethanolate and OAc=acetate] has been synthesized by the interaction of Cu(OAc)2 ·H2O with Ba(dmae)2 in toluene for the low temperature deposition of CuO–Ba2Cu3O5+ x composite thin films. Complex (1) was characterized by melting point, elemental analysis, FT-IR spectroscopy, mass spectrometry, thermal analysis (TGA) and single crystal X-ray diffraction. Complex (1) crystallizes in the triclinic space group . A TGA study demonstrated that the complex undergoes controlled thermal decomposition at 400°C to give the CuO–Ba2Cu3O5+ x composite. The chemical composition and surface morphology of the deposited mixed oxide thin films were analyzed by scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and X-ray powder diffraction (XRPD), which support the formation of the pure crystalline CuO–Ba2Cu3O5+ x composite with particle sizes ranging from 0.08 to 0.4μm. The thickness and voltage–current characteristics of the thin films were determined with a profilometer and a voltmeter using the four-probe method, respectively. [Copyright &y& Elsevier]