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Graziella Malandrino - One of the best experts on this subject based on the ideXlab platform.

  • synthesis characterization and mass transport properties of a self generating single source magnesium precursor for mocvd of mgf2 films
    Chemistry of Materials, 2009
    Co-Authors: Maria Elena Fragala, Roberta G Toro, Patrizia Rossi, Paolo Dapporto, Graziella Malandrino
    Abstract:

    The Diglyme [CH3O(CH2CH2O)2CH3] adduct of the magnesium bis-hexafluoroacetyl-acetonato [Mg(hfa)2·2H2O·2Diglyme] has been synthesized in a single-step reaction. It has been characterized by elemental analyses, IR spectroscopy, and 1H and 13C NMR. Single-crystal X-ray diffraction studies provide evidence of a mononuclear hexa-coordinated complex with an octahedral structure for the Mg(hfa)2·2H2O moiety and Diglyme coordinated in the outer sphere (triclinic system, space group= P1; a = 8.952(3) A, b = 9.036(3) A, c = 11.98(1) A, α = 110.44(5)°, β = 108.64(4)°, γ = 97.06(3)°, Z = 1). The “thermal robustness” and mass transport properties of the adduct have been investigated by thermogravimetric analysis and chemical vapor deposition experiments. Thermal analysis data revealed high volatility and good thermal stability with a residue left lower than 1%. The Mg(hfa)2·2H2O·2Diglyme has been successfully applied to the low-pressure metal-organic chemical vapor deposition (MOCVD) of MgF2 films. The good quality o...

  • Yttrium β-Diketonate Glyme MOCVD Precursors: Effects of the Polyether Length on Stabilities, Mass Transport Properties and Coordination Spheres
    European Journal of Inorganic Chemistry, 2004
    Co-Authors: Graziella Malandrino, Ignazio L. Fragalà, Raffaella Lo Nigro, Cristiano Benelli
    Abstract:

    The glyme adducts of trishexafluoroacetylacetonato yttrium, [Y(hfa)3·monoglyme], [Y(hfa)3·Diglyme], [Y(hfa)3·(H2O)2·triglyme] and [Y(hfa)2·tetraglyme]+[Y(hfa)4]− {CH3(OCH2CH2)nOCH3, n = 1 monoglyme, 2 Diglyme, 3 triglyme and 4 tetraglyme}, were synthesized and characterized by elemental analysis, mass spectrometry, and IR, 1H and 13C NMR spectroscopy. Additionally, [Y(hfa)3·monoglyme] and [Y(hfa)3·Diglyme] were characterized by single-crystal X-ray diffraction studies. The mass-transport properties of these adducts were investigated by thermogravimetric analysis, differential scanning calorimetry, evaporation-rate measurements and chemical vapour-deposition experiments. There is evidence of high volatility and very good thermal stabilities with a residue lower than 2−4 %. Vaporization-rate experiments proved that all adducts are well-suited for metal-organic chemical vapour-deposition experiments. The [Y(hfa)3·monoglyme] complex was successfully applied in the low-pressure MOCVD process of YBaCuO HTc superconductor using a multimetal molten single source. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

  • Synthesis, Characterization, Crystal Structure and Mass Transport Properties of Lanthanum β-Diketonate Glyme Complexes, Volatile Precursors for Metal−Organic Chemical Vapor Deposition Applications
    Chemistry of Materials, 1998
    Co-Authors: Graziella Malandrino, Cristiano Benelli, And Francesco Castelli, Ignazio L. Fragalà
    Abstract:

    The monoglyme {CH3OCH2CH2OCH3}, Diglyme {CH3O(CH2CH2O)2CH3}, and triglyme {CH3O(CH2CH2O)3CH3} adducts of the lanthanum trishexafluoroacetylacetonato {La(hfa)3·monoglyme·H2O, La(hfa)3·Diglyme and La(hfa)3·triglyme} have been synthesized in a single-step reaction. They have been characterized by elemental analyses, mass spectrometry, IR spectroscopy, 1H and 13C NMR spectroscopy. Single-crystal X-ray diffraction studies provide evidence of a mononuclear 9-coordinated complex with a monocapped square antiprismatic structure for the La(hfa)3·Diglyme (monoclinic system, space group = P21/c; a = 10.075(2) A, b = 15.599(4) A, c = 21.038(9) A, β = 103.48(5)°, Z = 4). The La(hfa)3·monoglyme·H2O consists of asymmetric units containing two similar molecules (monoclinic system, space group = P21/c; a = 21.812(7) A, b = 13.232(3) A, c = 22.100(6) A, β= 111.28(4)°, Z = 4), while a more complex structure having asymmetric tetramolecular units has been found in the case of the La(hfa)3·triglyme (monoclinic system, space g...

  • Synthesis, Characterization, and Mass-Transport Properties of Two Novel Gadolinium(III) Hexafluoroacetylacetonate Polyether Adducts: Promising Precursors for MOCVD of GdF3 Films
    Chemistry of Materials, 1996
    Co-Authors: Graziella Malandrino, Ignazio L. Fragalà, Ornella Incontro, Francesco Castelli, Cristiano Benelli
    Abstract:

    The monoglyme {CH3OCH2CH2OCH3} and Diglyme {CH3O(CH2CH2O)2CH3} adducts of the gadolinium trishexafluoroacetylacetonate {Gd(hfa)3·monoglyme (1) and Gd(hfa)3·Diglyme (2)} have been synthesized and characterized by elemental analyses, mass spectrometry, and infrared spectroscopy. Single-crystal X-ray diffraction studies of Gd(hfa)3·Diglyme provide evidence of a mononuclear structure. The thermal analyses revealed high volatility and good thermal stability with a low residue for both compounds. The adducts 1 and 2 have better mass-transport properties and thermal behaviors than conventional rare-earth MOCVD precursors and have been successfully applied to GdF3 film depositions. They represent the first examples of gadolinium precursors that can be used in the liquid phase without decomposition, thus providing constant evaporation rates even for very long deposition times.

Stéphane Daniele - One of the best experts on this subject based on the ideXlab platform.

  • influence of na ion doping on the phase change and upconversion emissions of the gdf3 yb3 tm3 nanocrystals obtained from the designed molecular precursors
    RSC Advances, 2015
    Co-Authors: Hana Ayadi, Wenzhang Fang, Shashank Mishra, Erwann Jeanneau, Gilles Ledoux, Jinlong Zhang, Stéphane Daniele
    Abstract:

    Bottom-up synthesis of a series of GdF3 nanocrystals (NCs) co-doped with 20 mol% Yb3+, 2 mol% Tm3+ and varying amount of Na+ ions is reported using novel molecular precursors [Ln2(TFA)6(Diglyme)2] [Ln = Gd (1), Tm (2), Yb (3)] and [Na4(TFA)4(Diglyme)]∞ (4) [TFA = CF3COO−; Diglyme = MeO(CH2CH2O)2Me]. The single crystal X-ray structures of the new complexes 1–4, which act as excellent precursors because of the absence of water molecules and the ability of the Diglyme ligand to behave as a capping reagent during decomposition to render the nanoparticles monodisperse in organic solvents, show a versatile bonding mode of the TFA (dangling η1 or bridging μ,η1,η1; μ4-η1:η1:η1:η1- and μ4-η1:η1:η1:η2 (O, F)) and Diglyme (η3 or μ-η3:η1) ligands. The influence of Na+ ion doping on the phase change and upconversion emissions of these GdF3: Yb3+, Tm3+ NCs was studied and compared with the upconversion (UC) intensity of the well-known upconverting NaGdF4: Yb3+, Tm3+ NCs. Among the several UC samples studied, the GdF3: Yb3+, Tm3+ NCs with 30 mol% Na+ seemed to be the most promising as a red emitting UC phosphor, emitting more photons than the NaGdF4: Yb3+, Tm3+ UC NCs in the near IR region.

  • Influence of Na+ ion doping on the phase change and upconversion emissions of the GdF3: Yb3+, Tm3+ nanocrystals obtained from the designed molecular precursors
    RSC Adv., 2015
    Co-Authors: Hana Ayadi, Wenzhang Fang, Shashank Mishra, Erwann Jeanneau, Gilles Ledoux, Jinlong Zhang, Stéphane Daniele
    Abstract:

    Bottom-up synthesis of a series of GdF3 nanocrystals (NCs) co-doped with 20 mol% Yb3+, 2 mol% Tm3+ and varying amount of Na+ ions is reported using novel molecular precursors [Ln2(TFA)6(Diglyme)2] [Ln = Gd (1), Tm (2), Yb (3)] and [Na4(TFA)4(Diglyme)]∞ (4) [TFA = CF3COO−; Diglyme = MeO(CH2CH2O)2Me]. The single crystal X-ray structures of the new complexes 1–4, which act as excellent precursors because of the absence of water molecules and the ability of the Diglyme ligand to behave as a capping reagent during decomposition to render the nanoparticles monodisperse in organic solvents, show a versatile bonding mode of the TFA (dangling η1 or bridging μ,η1,η1; μ4-η1:η1:η1:η1- and μ4-η1:η1:η1:η2 (O, F)) and Diglyme (η3 or μ-η3:η1) ligands. The influence of Na+ ion doping on the phase change and upconversion emissions of these GdF3: Yb3+, Tm3+ NCs was studied and compared with the upconversion (UC) intensity of the well-known upconverting NaGdF4: Yb3+, Tm3+ NCs. Among the several UC samples studied, the GdF3: Yb3+, Tm3+ NCs with 30 mol% Na+ seemed to be the most promising as a red emitting UC phosphor, emitting more photons than the NaGdF4: Yb3+, Tm3+ UC NCs in the near IR region.

Wenzhang Fang - One of the best experts on this subject based on the ideXlab platform.

  • influence of na ion doping on the phase change and upconversion emissions of the gdf3 yb3 tm3 nanocrystals obtained from the designed molecular precursors
    RSC Advances, 2015
    Co-Authors: Hana Ayadi, Wenzhang Fang, Shashank Mishra, Erwann Jeanneau, Gilles Ledoux, Jinlong Zhang, Stéphane Daniele
    Abstract:

    Bottom-up synthesis of a series of GdF3 nanocrystals (NCs) co-doped with 20 mol% Yb3+, 2 mol% Tm3+ and varying amount of Na+ ions is reported using novel molecular precursors [Ln2(TFA)6(Diglyme)2] [Ln = Gd (1), Tm (2), Yb (3)] and [Na4(TFA)4(Diglyme)]∞ (4) [TFA = CF3COO−; Diglyme = MeO(CH2CH2O)2Me]. The single crystal X-ray structures of the new complexes 1–4, which act as excellent precursors because of the absence of water molecules and the ability of the Diglyme ligand to behave as a capping reagent during decomposition to render the nanoparticles monodisperse in organic solvents, show a versatile bonding mode of the TFA (dangling η1 or bridging μ,η1,η1; μ4-η1:η1:η1:η1- and μ4-η1:η1:η1:η2 (O, F)) and Diglyme (η3 or μ-η3:η1) ligands. The influence of Na+ ion doping on the phase change and upconversion emissions of these GdF3: Yb3+, Tm3+ NCs was studied and compared with the upconversion (UC) intensity of the well-known upconverting NaGdF4: Yb3+, Tm3+ NCs. Among the several UC samples studied, the GdF3: Yb3+, Tm3+ NCs with 30 mol% Na+ seemed to be the most promising as a red emitting UC phosphor, emitting more photons than the NaGdF4: Yb3+, Tm3+ UC NCs in the near IR region.

  • Influence of Na+ ion doping on the phase change and upconversion emissions of the GdF3: Yb3+, Tm3+ nanocrystals obtained from the designed molecular precursors
    RSC Adv., 2015
    Co-Authors: Hana Ayadi, Wenzhang Fang, Shashank Mishra, Erwann Jeanneau, Gilles Ledoux, Jinlong Zhang, Stéphane Daniele
    Abstract:

    Bottom-up synthesis of a series of GdF3 nanocrystals (NCs) co-doped with 20 mol% Yb3+, 2 mol% Tm3+ and varying amount of Na+ ions is reported using novel molecular precursors [Ln2(TFA)6(Diglyme)2] [Ln = Gd (1), Tm (2), Yb (3)] and [Na4(TFA)4(Diglyme)]∞ (4) [TFA = CF3COO−; Diglyme = MeO(CH2CH2O)2Me]. The single crystal X-ray structures of the new complexes 1–4, which act as excellent precursors because of the absence of water molecules and the ability of the Diglyme ligand to behave as a capping reagent during decomposition to render the nanoparticles monodisperse in organic solvents, show a versatile bonding mode of the TFA (dangling η1 or bridging μ,η1,η1; μ4-η1:η1:η1:η1- and μ4-η1:η1:η1:η2 (O, F)) and Diglyme (η3 or μ-η3:η1) ligands. The influence of Na+ ion doping on the phase change and upconversion emissions of these GdF3: Yb3+, Tm3+ NCs was studied and compared with the upconversion (UC) intensity of the well-known upconverting NaGdF4: Yb3+, Tm3+ NCs. Among the several UC samples studied, the GdF3: Yb3+, Tm3+ NCs with 30 mol% Na+ seemed to be the most promising as a red emitting UC phosphor, emitting more photons than the NaGdF4: Yb3+, Tm3+ UC NCs in the near IR region.

Cristiano Benelli - One of the best experts on this subject based on the ideXlab platform.

  • Yttrium β-Diketonate Glyme MOCVD Precursors: Effects of the Polyether Length on Stabilities, Mass Transport Properties and Coordination Spheres
    European Journal of Inorganic Chemistry, 2004
    Co-Authors: Graziella Malandrino, Ignazio L. Fragalà, Raffaella Lo Nigro, Cristiano Benelli
    Abstract:

    The glyme adducts of trishexafluoroacetylacetonato yttrium, [Y(hfa)3·monoglyme], [Y(hfa)3·Diglyme], [Y(hfa)3·(H2O)2·triglyme] and [Y(hfa)2·tetraglyme]+[Y(hfa)4]− {CH3(OCH2CH2)nOCH3, n = 1 monoglyme, 2 Diglyme, 3 triglyme and 4 tetraglyme}, were synthesized and characterized by elemental analysis, mass spectrometry, and IR, 1H and 13C NMR spectroscopy. Additionally, [Y(hfa)3·monoglyme] and [Y(hfa)3·Diglyme] were characterized by single-crystal X-ray diffraction studies. The mass-transport properties of these adducts were investigated by thermogravimetric analysis, differential scanning calorimetry, evaporation-rate measurements and chemical vapour-deposition experiments. There is evidence of high volatility and very good thermal stabilities with a residue lower than 2−4 %. Vaporization-rate experiments proved that all adducts are well-suited for metal-organic chemical vapour-deposition experiments. The [Y(hfa)3·monoglyme] complex was successfully applied in the low-pressure MOCVD process of YBaCuO HTc superconductor using a multimetal molten single source. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

  • Synthesis, Characterization, Crystal Structure and Mass Transport Properties of Lanthanum β-Diketonate Glyme Complexes, Volatile Precursors for Metal−Organic Chemical Vapor Deposition Applications
    Chemistry of Materials, 1998
    Co-Authors: Graziella Malandrino, Cristiano Benelli, And Francesco Castelli, Ignazio L. Fragalà
    Abstract:

    The monoglyme {CH3OCH2CH2OCH3}, Diglyme {CH3O(CH2CH2O)2CH3}, and triglyme {CH3O(CH2CH2O)3CH3} adducts of the lanthanum trishexafluoroacetylacetonato {La(hfa)3·monoglyme·H2O, La(hfa)3·Diglyme and La(hfa)3·triglyme} have been synthesized in a single-step reaction. They have been characterized by elemental analyses, mass spectrometry, IR spectroscopy, 1H and 13C NMR spectroscopy. Single-crystal X-ray diffraction studies provide evidence of a mononuclear 9-coordinated complex with a monocapped square antiprismatic structure for the La(hfa)3·Diglyme (monoclinic system, space group = P21/c; a = 10.075(2) A, b = 15.599(4) A, c = 21.038(9) A, β = 103.48(5)°, Z = 4). The La(hfa)3·monoglyme·H2O consists of asymmetric units containing two similar molecules (monoclinic system, space group = P21/c; a = 21.812(7) A, b = 13.232(3) A, c = 22.100(6) A, β= 111.28(4)°, Z = 4), while a more complex structure having asymmetric tetramolecular units has been found in the case of the La(hfa)3·triglyme (monoclinic system, space g...

  • Synthesis, Characterization, and Mass-Transport Properties of Two Novel Gadolinium(III) Hexafluoroacetylacetonate Polyether Adducts: Promising Precursors for MOCVD of GdF3 Films
    Chemistry of Materials, 1996
    Co-Authors: Graziella Malandrino, Ignazio L. Fragalà, Ornella Incontro, Francesco Castelli, Cristiano Benelli
    Abstract:

    The monoglyme {CH3OCH2CH2OCH3} and Diglyme {CH3O(CH2CH2O)2CH3} adducts of the gadolinium trishexafluoroacetylacetonate {Gd(hfa)3·monoglyme (1) and Gd(hfa)3·Diglyme (2)} have been synthesized and characterized by elemental analyses, mass spectrometry, and infrared spectroscopy. Single-crystal X-ray diffraction studies of Gd(hfa)3·Diglyme provide evidence of a mononuclear structure. The thermal analyses revealed high volatility and good thermal stability with a low residue for both compounds. The adducts 1 and 2 have better mass-transport properties and thermal behaviors than conventional rare-earth MOCVD precursors and have been successfully applied to GdF3 film depositions. They represent the first examples of gadolinium precursors that can be used in the liquid phase without decomposition, thus providing constant evaporation rates even for very long deposition times.

Erwann Jeanneau - One of the best experts on this subject based on the ideXlab platform.

  • influence of na ion doping on the phase change and upconversion emissions of the gdf3 yb3 tm3 nanocrystals obtained from the designed molecular precursors
    RSC Advances, 2015
    Co-Authors: Hana Ayadi, Wenzhang Fang, Shashank Mishra, Erwann Jeanneau, Gilles Ledoux, Jinlong Zhang, Stéphane Daniele
    Abstract:

    Bottom-up synthesis of a series of GdF3 nanocrystals (NCs) co-doped with 20 mol% Yb3+, 2 mol% Tm3+ and varying amount of Na+ ions is reported using novel molecular precursors [Ln2(TFA)6(Diglyme)2] [Ln = Gd (1), Tm (2), Yb (3)] and [Na4(TFA)4(Diglyme)]∞ (4) [TFA = CF3COO−; Diglyme = MeO(CH2CH2O)2Me]. The single crystal X-ray structures of the new complexes 1–4, which act as excellent precursors because of the absence of water molecules and the ability of the Diglyme ligand to behave as a capping reagent during decomposition to render the nanoparticles monodisperse in organic solvents, show a versatile bonding mode of the TFA (dangling η1 or bridging μ,η1,η1; μ4-η1:η1:η1:η1- and μ4-η1:η1:η1:η2 (O, F)) and Diglyme (η3 or μ-η3:η1) ligands. The influence of Na+ ion doping on the phase change and upconversion emissions of these GdF3: Yb3+, Tm3+ NCs was studied and compared with the upconversion (UC) intensity of the well-known upconverting NaGdF4: Yb3+, Tm3+ NCs. Among the several UC samples studied, the GdF3: Yb3+, Tm3+ NCs with 30 mol% Na+ seemed to be the most promising as a red emitting UC phosphor, emitting more photons than the NaGdF4: Yb3+, Tm3+ UC NCs in the near IR region.

  • Influence of Na+ ion doping on the phase change and upconversion emissions of the GdF3: Yb3+, Tm3+ nanocrystals obtained from the designed molecular precursors
    RSC Adv., 2015
    Co-Authors: Hana Ayadi, Wenzhang Fang, Shashank Mishra, Erwann Jeanneau, Gilles Ledoux, Jinlong Zhang, Stéphane Daniele
    Abstract:

    Bottom-up synthesis of a series of GdF3 nanocrystals (NCs) co-doped with 20 mol% Yb3+, 2 mol% Tm3+ and varying amount of Na+ ions is reported using novel molecular precursors [Ln2(TFA)6(Diglyme)2] [Ln = Gd (1), Tm (2), Yb (3)] and [Na4(TFA)4(Diglyme)]∞ (4) [TFA = CF3COO−; Diglyme = MeO(CH2CH2O)2Me]. The single crystal X-ray structures of the new complexes 1–4, which act as excellent precursors because of the absence of water molecules and the ability of the Diglyme ligand to behave as a capping reagent during decomposition to render the nanoparticles monodisperse in organic solvents, show a versatile bonding mode of the TFA (dangling η1 or bridging μ,η1,η1; μ4-η1:η1:η1:η1- and μ4-η1:η1:η1:η2 (O, F)) and Diglyme (η3 or μ-η3:η1) ligands. The influence of Na+ ion doping on the phase change and upconversion emissions of these GdF3: Yb3+, Tm3+ NCs was studied and compared with the upconversion (UC) intensity of the well-known upconverting NaGdF4: Yb3+, Tm3+ NCs. Among the several UC samples studied, the GdF3: Yb3+, Tm3+ NCs with 30 mol% Na+ seemed to be the most promising as a red emitting UC phosphor, emitting more photons than the NaGdF4: Yb3+, Tm3+ UC NCs in the near IR region.

  • A molecular precursor approach to monodisperse scintillating CeF3 nanocrystals
    Dalton Transactions, 2013
    Co-Authors: S. Mishra, Erwann Jeanneau, A. L. Bulin, G. Ledoux, B. Jouguet, David Amans, A. Belsky, S. Daniele, Christophe Dujardin
    Abstract:

    A series of anhydrous cerium(III) trifluoroacetate complexes with neutral O-donor ligands, namely Ce-2(OAc)(TFA)(5)(DMF)(3) (1), Ce(TFA)(3)(L)(x) [x = 2, L = THF (2), DMF (3), DMSO (4); x = 1, L = Diglyme (5)] and Ce-2(TFA)(6)(DMSO)(x)(DMF)(y) [x = 6, y = 0 (6); x = 4, y = 2 (7)] (where OAc = acetate, TFA = trifluoroacetate, THF = tetrahydrofuran, DMF = dimethylformamide, DMSO = dimethylsulphoxide, and Diglyme = MeO(C2H4O)(2)Me] were synthesized and completely characterized by elemental analysis, FT-IR spectroscopy and TG-DTA-MS studies. A partially hydrated complex [Ce(TFA)(3)(Diglyme)(H2O)] (8) was obtained by slow evaporation of the THF solution of anhydrous 5 in the air. The single crystal X-ray diffraction analysis of 1, 3, 4, and 6-8 showed the versatile bonding mode of the TFA ligand (terminal, chelating and bridging). These complexes, on decomposition in 1-octadecene in inert atmosphere, gave CeF3 nanoparticles of 8-11 nm size. The complex 5 proved to be the best precursor in the series because of the ability of the Diglyme ligand to act as capping reagent during decomposition to render the CeF3 particles monodisperse in organic solvents. The obtained CeF3 nanoparticles were characterized by FT-IR, EDX analysis and TEM studies and their luminescence and scintillation responses under UV and X-ray excitation were studied and compared with that of CeF3 single crystal.