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Chemical Vapour Deposition (CVD) of metallic layers prepared from silver carboxylates complexes with tertiary phosphines

Szczęsny R., Szymańska I., Piszczek P., Dobrzańska L., Szłyk E.

Materials Science Poland

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2005

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Vol. 23, No. 3

671--676

EN

Silver fluorocarboxylate tertiary phosphines complexes [Ag(O2CR)(PR,3)] (where R = CF3, C2F5, Me3SiCH2; R, = Me, Et) have been used as precursors in the hot-wall Chemical Vapour Deposition (CVD) of silver films. Pyrolysis of Ag(I) compounds and thermal stability of metallic species transported in the gas phase were characterized by temperature variable IR (VT-IR) and MS (MS-EI) methods. Metallic films were produced between 403 and 423 K under deposition pressure 0.8 2.0 mbar, under Ar atmosphere, on Si(111) substrates. They were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) integrated with EDX equipment.

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Synthesis and Characterization of New Thiocyanato Bridged Complexes with the General Formula [MLn}3[Cr(NCS)6]2.mH2O, where M=Cu(II), Ni(II), Co(II); L=Various Substituted Imidazoles

Wrzeszcz G., Dobrzańska L., Grodzicki A., Rozpłoch F.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 2

147-156

EN

New thiocyanato bridged complexes of the type [CuL4]3[Cr(NCS)6]2_mH2O [L = 1-methylimidazole (1-Meim), 2-methylimidazole (2-Meim), 1,2-dimethylimidazole (1,2- Me2im)] and [M(1-Meim)6]n[{M(1-Meim)4Cr(NCS)6}2n]_mH2O (M = Ni(II), Co(II) were prepared by the reaction of [Cr(NCS)6]3- with the appropriate [MLn]2+ complex in an aqueous solution and characterized by elemental and thermal analysis, IR, UV-VIS, EPR and temperature variable magnetic susceptibility. The presence of NCS bridges between M(II)-Cr(III) centres is evident from IR spectra. The electronic spectra correlate with proposal of different composition of Cu3Cr2 and M3Cr2(M = Ni, Co) systems. The parameters determined from temperature dependence on magnetic susceptibility (80-300 K) indicate weak or negligible antiferromagnetic interaction for obtained Cu(II)-Cr(III), Ni(II)-Cr(III) and Co(II)-Cr(III) systems. Thermal decomposition after dehydration is multistage and yields CuO + CuCrO2 and MIIO+MIICr2O4 as final products, respectively.

3

Spectroscopic, Magnetic and Thermal Properties of New Thiocyanato Bridged Complexes of the Type [M(diamine)2]3[Cr(NCS)6]2.nH2O4, where M=Cu(II), Ni(II)

Wrzeszcz G., Dobrzańska L.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 10

1245-1254

EN

Heteropolynuclear complexes of the type [M(diamine)2]3[Cr(NCS)6]2_nH2O, where diamine = N-methylethylenediamine (N-Me-en), 1,2-diaminopropane (pn); M = Ni(II), Cu(II) have been prepared by reacting [Cr(NCS)6]3- with the corresponding cationic [M(diamine)2]2+ complex in an aqueous solution. They have been characterized by elemental analysis, IR, UV-VIS, EPR, variable temperature magnetic susceptibility and thermal analysis. Spectroscopic studies reveal thiocyanato bridges between M(II)-Cr(III) centres. The parameters determined from temperature dependence on magnetic susceptibility (80-300 K) indicate moderate antiferromagnetic interactions for Ni(II)-Cr(III) and negligibly small or very weak ones for Cu(II)-Cr(III) systems. Magnetic studies suggest also presence of diamagnetic Ni(II) ions in the structure of Ni(II)-pn-Cr(III) complex. Thermal analysis shows higher thermal stability of Ni(II)-Cr(III) than Cu(II)-Cr(III) compounds. The process of thermal decomposition after dehydration is multistage and yields NiO + NiCr2O4and CuO + CuCrO2 as final products, respectively.

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Synthesis, Spectroscopy and Magnetism of New -Thiocyanato Polynuclear Copper(II)-Chromium(III) Complexes

Dobrzańska L., Wrzeszcz G., Grodzicki A., Rozpłoch F.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 11

1689-1694

EN

New heteropolynuclear complexes with general formula [Cu(diamine)2]3 [Cr(NCS)6]2źnH2O, where diamine = N,N-dimethylethylenediamine (1,2-dmen), N,N-dimethylethylenediamine (1,1-dmen), N,N-diethylethylenediamine (1,2-deen), N,N-diethylethylenediamine (1,1-deen), 1,3-diaminopropane (tn) were obtained by reactions of [Cr(NCS)6]3– with the corresponding cationic Cu(II) complexes: [Cu(diamine)2]2+ and characterized by spectroscopic methods and magnetic measurements. The formation of end-to-end thiocyanato bridges between tetragonal Cu(II) and pseudo-octahedral Cr(III) is evident from IR and UV-VIS spectra by appearance of new components of ni(CN) band and shifts in the absorption maxima assigned to copper d-d transitions in comparison with corresponding mononuclear complexes. The EPR spectra measured at room temperature on solid samples show broad, symmetric signal at g = 2.02–2.03.Variable-temperature magnetic susceptibility measurements reveal the presence of weak antiferromagnetic interactions in [Cu(1,1-deen)2]3[Cr(NCS)6]2H2O and [Cu(tn)2]3[Cr(NCS)6]22H2O.

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Synthesis and Properties of New Bimetallic Complexes of General Formula: [Ni(diamine)2]3[Cr(NCS)6]2.nH2O

Dobrzańska L., Wrzeszcz G., Grodzicki A., Rozpłoch F.

Polish Journal of Chemistry

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2001

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Vol. 75, nr 6

909-914

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Synthesis and Characterization of Thiocyanato-Bridged Heteropolynuclear Chromium(III)-Copper(II) Complexes

Dobrzańska L., Wrzeszcz G., Grodzicki A., Rozpłoch F.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 2

199-206

EN

Heteropolynuclear thiocyanate-bridged complexes were prepared in the reactions of aqueous solutions of K3[Cr(NCS)6] with copper(II) complexes of the type [CuX4]2+, where X=imidazole (imH), 4-methylimidazole (4-MeimH) and 2X= ethylenediamine (en). Solid products were formulated as (Cu(imH)4)3(Cr(NCS)6)2 *2H2O, (Cu(4-MeimH)4)3(Cr(NCS)6)2 *3H2O and (Cu(en)2)3(Cr(NCS)6)2 *2H2O on the basis of elemental analysis and spectral data (IR,UV-VIS). EPR spectra, variable temperature magnetic susceptibility and thermal properties in air were investigated, indicating that all complexes are polynuclear with thiocyanate bridges, exhibiting Curie-Weiss behavior between 80-300 K. Thermal decomposition is multistage and yields CuO and CuCrO2 as final products.