The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
Junhua Luo - One of the best experts on this subject based on the ideXlab platform.
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dibenzylammonium Trichloroacetate an above room temperature order disorder switchable dielectric material
CrystEngComm, 2016Co-Authors: Siyuan Zeng, Zhihua Sun, Shuquan Zhang, Cheng Song, Junhua LuoAbstract:Solid-state phase transition materials with a controllable dielectric response are of great interest owing to their technological importance. In the present work, a new molecular electric-ordered compound, dibenzylammonium Trichloroacetate (compound 1), showing switchable and tunable dielectric properties, has been successfully synthesized and grown as bulk crystals. It is found that 1 undergoes a reversible solid-to-solid phase transition at 329 K (Tc), which was confirmed by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature powder X-ray diffraction. Structural analyses reveal that intermolecular N–H⋯O hydrogen bonds connect the functional groups together and form a chain-like supramolecular architecture along the a-axis. Further, variable-temperature single-crystal X-ray diffraction discloses the order–disorder feature of its structural change, which is mainly induced by the disordering of Trichloroacetate anions upon gradual heating. Moreover, the dielectric constants of 1 display a step-like anomaly around Tc, suggesting that its dielectric responses could be switched or even tuned by external temperature. It is believed that this finding might provide a possible candidate with controllable dielectric performance for potential application.
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Dibenzylammonium Trichloroacetate: an above-room-temperature order–disorder switchable dielectric material
CrystEngComm, 2016Co-Authors: Siyuan Zeng, Zhihua Sun, Shuquan Zhang, Cheng Song, Junhua LuoAbstract:Solid-state phase transition materials with a controllable dielectric response are of great interest owing to their technological importance. In the present work, a new molecular electric-ordered compound, dibenzylammonium Trichloroacetate (compound 1), showing switchable and tunable dielectric properties, has been successfully synthesized and grown as bulk crystals. It is found that 1 undergoes a reversible solid-to-solid phase transition at 329 K (Tc), which was confirmed by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature powder X-ray diffraction. Structural analyses reveal that intermolecular N–H⋯O hydrogen bonds connect the functional groups together and form a chain-like supramolecular architecture along the a-axis. Further, variable-temperature single-crystal X-ray diffraction discloses the order–disorder feature of its structural change, which is mainly induced by the disordering of Trichloroacetate anions upon gradual heating. Moreover, the dielectric constants of 1 display a step-like anomaly around Tc, suggesting that its dielectric responses could be switched or even tuned by external temperature. It is believed that this finding might provide a possible candidate with controllable dielectric performance for potential application.
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Order–disorder phase transition coupled with torsion in tri-n-butylammonium Trichloroacetate (TBAT)
Journal of Materials Chemistry C, 2015Co-Authors: Muhammad Adnan Asghar, Yuelan Zhou, Zhihua Sun, Tariq Khan, Shuquan Zhang, Sangen Zhao, Junhua LuoAbstract:Tri-n-butylammonium Trichloroacetate (TBAT), a novel hybrid material, undergoes a reversible phase transition around 196 K, which is triggered by torsion in the cations and the order–disorder transformations of both ions.
Valeria Ferretti - One of the best experts on this subject based on the ideXlab platform.
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Thermal studies and decomposition kinetics of alkaline earth metal Trichloroacetates
Journal of Thermal Analysis and Calorimetry, 2014Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Valeria FerrettiAbstract:Alkaline earth metal Trichloroacetates M(O2CCCCl3)2.nH2O, where M = Be (1), n = 4; M = Mg (2), n = 6; M = Ca (3) or Sr(4) or Ba(5), n = 4, were synthesized and their thermal behavior analyzed using thermogravimetric analysis (TG/DTG/DSC). A critical examination was made for the apparent activation energy by means of non-isothermal kinetic methods employing multiple heating rates. A systematic and comparative study of thermal decomposition was carried out at different heating rates i.e., 5, 10, 15, and 20 °C min-1 for various Trichloroacetates synthesized. It was observed that the Ca, Sr, and Ba Trichloroacetates decompose preferentially to respective metal halides while Be and Mg compounds decompose to metal and metal oxide, respectively. The composition of the final residues was also confirmed using FT-IR spectroscopy. The activation energy follows the order: Mg> Ca> Sr> Ba, Be being the exception. Results reveal that each metal Trichloroacetate decomposes through its unique thermolysis mechanism
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Synthesis and characterization of alkaline earth metal Trichloroacetates
Inorganica Chimica Acta, 2014Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Ghazalpreet Kaur, Valeria FerrettiAbstract:Abstract Alkaline earth metal Trichloroacetates M(O2CCCl3)2·nH2O where M = Be (1), n = 4; M = Mg (2), n = 6; M = Ca (3) or Sr (4) or Ba (5), n = 4 were synthesized by reacting BeSO4 with hydrated barium Trichloroacetate for 1 and neutralization of respective metal carbonates with trichloroacetic acid for 2–5. The desired products were characterized by elemental analysis, physiochemical studies, FT-IR, 13C NMR and single crystal X-ray studies (in case of 2, 3 and 4). The spectroscopic data reveals bidentate bridging CCl3COO groups and coordinated water molecules in Be(O2CCl3)2·4H2O. The compound 2 crystallizes in triclinic crystal system with space group, P 1 ¯ . The crystal structure reveals that magnesium cation is coordinated to six water molecules with regular octahedral geometry. All water molecules are involved in hydrogen bonding with oxygens of CCl3CO2 groups in 2. The compounds 3 and 4 are isostructural and each compound crystallizes in monoclinic crystal system with space group, P21/c, having similar cell parameters and showing the same spatial arrangement. The central metal ions are octacoordinated in 3 and 4. The bridging Trichloroacetate ligand in 3 and 4 results in the formation of polymeric chains giving rise to 1D infinite polymers. Similar environment is anticipated around barium cation in 5 as that of metal ion in 3 or 4 on the basis of similar physiochemical and spectroscopic results.
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synthesis characterization and molecular structures of barium ii Trichloroacetate dme 1 4 dioxane compounds
Polyhedron, 2012Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Valeria FerrettiAbstract:Abstract Two new barium(II) Trichloroacetate compounds, [Ba(H2O)(DME)(μ-O2CCCl3)2]n (1) and [{Ba(H2O)2(diox)0.5(μ-O2CCCl3)2}(diox)]n (2) were synthesized and characterized by elemental analyses, physiochemical studies, FT-IR, 1H NMR, thermogravimetric analyses (TG/DTG/DSC) and single crystal X-ray studies. The reaction of hydrated barium(II) Trichloroacetate monohydrate with excess DME (1,2-dimethoxyethane) and diox (1,4-dioxane) in methanol at room temperature led to the isolation of the novel compounds 1 and 2, respectively. Bridging Trichloroacetate groups are anticipated on the basis of FT-IR studies and this was confirmed by the X-ray studies. Both compounds dissociate to produce ions in water, as shown by molar conductance values. 1H NMR spectroscopy confirms that DME and 1,4-dioxane are coordinated to the metal ion in these compounds. Single crystal X-ray diffraction studies reveal that the barium cation is coordinated to nine O atoms in a deformed coordination polyhedron in both compounds. Structural data of barium(II) Trichloroacetates compounds have been obtained for the first time in the present investigation.
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Synthesis, characterization and molecular structures of barium(II) Trichloroacetate DME/1,4-dioxane compounds
Polyhedron, 2012Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Valeria FerrettiAbstract:Two new barium(II) Trichloroacetate compounds, [Ba(H2O)(DME)(μ-O2CCCl3)2]n (1) and [{Ba(H2O)2(diox)0.5(μ-O2CCCl3)2}(diox)]n (2) were synthesized and characterized by elemental analyses, physiochemical studies, FT-IR, 1H NMR, thermogravimetric analyses (TG/DTG/DSC) and single crystal X-ray studies. The reaction of hydrated barium(II) Trichloroacetate monohydrate with excess DME (1,2-dimethoxyethane) and diox (1,4-dioxane) in methanol at room temperature led to the isolation of the novel compounds 1 and 2, respectively. Bridging Trichloroacetate groups are anticipated on the basis of FT-IR studies and this was confirmed by the X-ray studies. Both compounds dissociate to produce ions in water, as shown by molar conductance values. 1H NMR spectroscopy confirms that DME and 1,4-dioxane are coordinated to the metal ion in these compounds. Single crystal X-ray diffraction studies reveal that the barium cation is coordinated to nine O atoms in a deformed coordination polyhedron in both compounds. Structural data of barium(II) Trichloroacetates compounds have been obtained for the first time in the present investigation
Sukhjinder Singh - One of the best experts on this subject based on the ideXlab platform.
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Thermal studies and decomposition kinetics of alkaline earth metal Trichloroacetates
Journal of Thermal Analysis and Calorimetry, 2014Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Valeria FerrettiAbstract:Alkaline earth metal Trichloroacetates M(O2CCCCl3)2.nH2O, where M = Be (1), n = 4; M = Mg (2), n = 6; M = Ca (3) or Sr(4) or Ba(5), n = 4, were synthesized and their thermal behavior analyzed using thermogravimetric analysis (TG/DTG/DSC). A critical examination was made for the apparent activation energy by means of non-isothermal kinetic methods employing multiple heating rates. A systematic and comparative study of thermal decomposition was carried out at different heating rates i.e., 5, 10, 15, and 20 °C min-1 for various Trichloroacetates synthesized. It was observed that the Ca, Sr, and Ba Trichloroacetates decompose preferentially to respective metal halides while Be and Mg compounds decompose to metal and metal oxide, respectively. The composition of the final residues was also confirmed using FT-IR spectroscopy. The activation energy follows the order: Mg> Ca> Sr> Ba, Be being the exception. Results reveal that each metal Trichloroacetate decomposes through its unique thermolysis mechanism
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Synthesis and characterization of alkaline earth metal Trichloroacetates
Inorganica Chimica Acta, 2014Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Ghazalpreet Kaur, Valeria FerrettiAbstract:Abstract Alkaline earth metal Trichloroacetates M(O2CCCl3)2·nH2O where M = Be (1), n = 4; M = Mg (2), n = 6; M = Ca (3) or Sr (4) or Ba (5), n = 4 were synthesized by reacting BeSO4 with hydrated barium Trichloroacetate for 1 and neutralization of respective metal carbonates with trichloroacetic acid for 2–5. The desired products were characterized by elemental analysis, physiochemical studies, FT-IR, 13C NMR and single crystal X-ray studies (in case of 2, 3 and 4). The spectroscopic data reveals bidentate bridging CCl3COO groups and coordinated water molecules in Be(O2CCl3)2·4H2O. The compound 2 crystallizes in triclinic crystal system with space group, P 1 ¯ . The crystal structure reveals that magnesium cation is coordinated to six water molecules with regular octahedral geometry. All water molecules are involved in hydrogen bonding with oxygens of CCl3CO2 groups in 2. The compounds 3 and 4 are isostructural and each compound crystallizes in monoclinic crystal system with space group, P21/c, having similar cell parameters and showing the same spatial arrangement. The central metal ions are octacoordinated in 3 and 4. The bridging Trichloroacetate ligand in 3 and 4 results in the formation of polymeric chains giving rise to 1D infinite polymers. Similar environment is anticipated around barium cation in 5 as that of metal ion in 3 or 4 on the basis of similar physiochemical and spectroscopic results.
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Synthesis and Characterization of Zinc(II) and Cadmium(II) Mixed Ligand Trichloroacetate Complexes
Synthesis and Reactivity in Inorganic Metal-Organic and Nano-Metal Chemistry, 2013Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Duane Choquesillo-lazarteAbstract:Mixed ligand, iso-structural zinc(II), [Zn(L1)2(L2)2] 1 and cadmium(II), [Cd(L1)2(L2)2] 2, (L1 = CCl3COO−, L2 = N,N,N′,N′-tetramethylethylenediamine (tmen)), Trichloroacetate complexes have been prepared and characterized by elemental, spectroscopic (ir, nmr), thermogravimetry, molar conductivity, and X-ray studies in 2. The Trichloroacetate acts as a monodentate and tmen ligand L2 functions as a bidentate ligand in both the complexes. The crystal structure of 2 is of monoclinic system, space group P21/n with a = 8.3302(19) Ǻ, b = 17.756(4) Ǻ, c = 18.619(4) Ǻ, β = 100.393(3)°, and V = 2708.8(10) Ǻ3, Z = 4. The geometry around the metal is distorted octahedral.
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synthesis characterization and molecular structures of barium ii Trichloroacetate dme 1 4 dioxane compounds
Polyhedron, 2012Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Valeria FerrettiAbstract:Abstract Two new barium(II) Trichloroacetate compounds, [Ba(H2O)(DME)(μ-O2CCCl3)2]n (1) and [{Ba(H2O)2(diox)0.5(μ-O2CCCl3)2}(diox)]n (2) were synthesized and characterized by elemental analyses, physiochemical studies, FT-IR, 1H NMR, thermogravimetric analyses (TG/DTG/DSC) and single crystal X-ray studies. The reaction of hydrated barium(II) Trichloroacetate monohydrate with excess DME (1,2-dimethoxyethane) and diox (1,4-dioxane) in methanol at room temperature led to the isolation of the novel compounds 1 and 2, respectively. Bridging Trichloroacetate groups are anticipated on the basis of FT-IR studies and this was confirmed by the X-ray studies. Both compounds dissociate to produce ions in water, as shown by molar conductance values. 1H NMR spectroscopy confirms that DME and 1,4-dioxane are coordinated to the metal ion in these compounds. Single crystal X-ray diffraction studies reveal that the barium cation is coordinated to nine O atoms in a deformed coordination polyhedron in both compounds. Structural data of barium(II) Trichloroacetates compounds have been obtained for the first time in the present investigation.
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Synthesis, characterization and molecular structures of barium(II) Trichloroacetate DME/1,4-dioxane compounds
Polyhedron, 2012Co-Authors: Sukhjinder Singh, Deepika Saini, S.k. Mehta, Ravneet Kaur, Valeria FerrettiAbstract:Two new barium(II) Trichloroacetate compounds, [Ba(H2O)(DME)(μ-O2CCCl3)2]n (1) and [{Ba(H2O)2(diox)0.5(μ-O2CCCl3)2}(diox)]n (2) were synthesized and characterized by elemental analyses, physiochemical studies, FT-IR, 1H NMR, thermogravimetric analyses (TG/DTG/DSC) and single crystal X-ray studies. The reaction of hydrated barium(II) Trichloroacetate monohydrate with excess DME (1,2-dimethoxyethane) and diox (1,4-dioxane) in methanol at room temperature led to the isolation of the novel compounds 1 and 2, respectively. Bridging Trichloroacetate groups are anticipated on the basis of FT-IR studies and this was confirmed by the X-ray studies. Both compounds dissociate to produce ions in water, as shown by molar conductance values. 1H NMR spectroscopy confirms that DME and 1,4-dioxane are coordinated to the metal ion in these compounds. Single crystal X-ray diffraction studies reveal that the barium cation is coordinated to nine O atoms in a deformed coordination polyhedron in both compounds. Structural data of barium(II) Trichloroacetates compounds have been obtained for the first time in the present investigation
Shuquan Zhang - One of the best experts on this subject based on the ideXlab platform.
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dibenzylammonium Trichloroacetate an above room temperature order disorder switchable dielectric material
CrystEngComm, 2016Co-Authors: Siyuan Zeng, Zhihua Sun, Shuquan Zhang, Cheng Song, Junhua LuoAbstract:Solid-state phase transition materials with a controllable dielectric response are of great interest owing to their technological importance. In the present work, a new molecular electric-ordered compound, dibenzylammonium Trichloroacetate (compound 1), showing switchable and tunable dielectric properties, has been successfully synthesized and grown as bulk crystals. It is found that 1 undergoes a reversible solid-to-solid phase transition at 329 K (Tc), which was confirmed by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature powder X-ray diffraction. Structural analyses reveal that intermolecular N–H⋯O hydrogen bonds connect the functional groups together and form a chain-like supramolecular architecture along the a-axis. Further, variable-temperature single-crystal X-ray diffraction discloses the order–disorder feature of its structural change, which is mainly induced by the disordering of Trichloroacetate anions upon gradual heating. Moreover, the dielectric constants of 1 display a step-like anomaly around Tc, suggesting that its dielectric responses could be switched or even tuned by external temperature. It is believed that this finding might provide a possible candidate with controllable dielectric performance for potential application.
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Dibenzylammonium Trichloroacetate: an above-room-temperature order–disorder switchable dielectric material
CrystEngComm, 2016Co-Authors: Siyuan Zeng, Zhihua Sun, Shuquan Zhang, Cheng Song, Junhua LuoAbstract:Solid-state phase transition materials with a controllable dielectric response are of great interest owing to their technological importance. In the present work, a new molecular electric-ordered compound, dibenzylammonium Trichloroacetate (compound 1), showing switchable and tunable dielectric properties, has been successfully synthesized and grown as bulk crystals. It is found that 1 undergoes a reversible solid-to-solid phase transition at 329 K (Tc), which was confirmed by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature powder X-ray diffraction. Structural analyses reveal that intermolecular N–H⋯O hydrogen bonds connect the functional groups together and form a chain-like supramolecular architecture along the a-axis. Further, variable-temperature single-crystal X-ray diffraction discloses the order–disorder feature of its structural change, which is mainly induced by the disordering of Trichloroacetate anions upon gradual heating. Moreover, the dielectric constants of 1 display a step-like anomaly around Tc, suggesting that its dielectric responses could be switched or even tuned by external temperature. It is believed that this finding might provide a possible candidate with controllable dielectric performance for potential application.
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Order–disorder phase transition coupled with torsion in tri-n-butylammonium Trichloroacetate (TBAT)
Journal of Materials Chemistry C, 2015Co-Authors: Muhammad Adnan Asghar, Yuelan Zhou, Zhihua Sun, Tariq Khan, Shuquan Zhang, Sangen Zhao, Junhua LuoAbstract:Tri-n-butylammonium Trichloroacetate (TBAT), a novel hybrid material, undergoes a reversible phase transition around 196 K, which is triggered by torsion in the cations and the order–disorder transformations of both ions.
Zhihua Sun - One of the best experts on this subject based on the ideXlab platform.
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dibenzylammonium Trichloroacetate an above room temperature order disorder switchable dielectric material
CrystEngComm, 2016Co-Authors: Siyuan Zeng, Zhihua Sun, Shuquan Zhang, Cheng Song, Junhua LuoAbstract:Solid-state phase transition materials with a controllable dielectric response are of great interest owing to their technological importance. In the present work, a new molecular electric-ordered compound, dibenzylammonium Trichloroacetate (compound 1), showing switchable and tunable dielectric properties, has been successfully synthesized and grown as bulk crystals. It is found that 1 undergoes a reversible solid-to-solid phase transition at 329 K (Tc), which was confirmed by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature powder X-ray diffraction. Structural analyses reveal that intermolecular N–H⋯O hydrogen bonds connect the functional groups together and form a chain-like supramolecular architecture along the a-axis. Further, variable-temperature single-crystal X-ray diffraction discloses the order–disorder feature of its structural change, which is mainly induced by the disordering of Trichloroacetate anions upon gradual heating. Moreover, the dielectric constants of 1 display a step-like anomaly around Tc, suggesting that its dielectric responses could be switched or even tuned by external temperature. It is believed that this finding might provide a possible candidate with controllable dielectric performance for potential application.
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Dibenzylammonium Trichloroacetate: an above-room-temperature order–disorder switchable dielectric material
CrystEngComm, 2016Co-Authors: Siyuan Zeng, Zhihua Sun, Shuquan Zhang, Cheng Song, Junhua LuoAbstract:Solid-state phase transition materials with a controllable dielectric response are of great interest owing to their technological importance. In the present work, a new molecular electric-ordered compound, dibenzylammonium Trichloroacetate (compound 1), showing switchable and tunable dielectric properties, has been successfully synthesized and grown as bulk crystals. It is found that 1 undergoes a reversible solid-to-solid phase transition at 329 K (Tc), which was confirmed by differential scanning calorimetry (DSC), dielectric measurements and variable-temperature powder X-ray diffraction. Structural analyses reveal that intermolecular N–H⋯O hydrogen bonds connect the functional groups together and form a chain-like supramolecular architecture along the a-axis. Further, variable-temperature single-crystal X-ray diffraction discloses the order–disorder feature of its structural change, which is mainly induced by the disordering of Trichloroacetate anions upon gradual heating. Moreover, the dielectric constants of 1 display a step-like anomaly around Tc, suggesting that its dielectric responses could be switched or even tuned by external temperature. It is believed that this finding might provide a possible candidate with controllable dielectric performance for potential application.
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Order–disorder phase transition coupled with torsion in tri-n-butylammonium Trichloroacetate (TBAT)
Journal of Materials Chemistry C, 2015Co-Authors: Muhammad Adnan Asghar, Yuelan Zhou, Zhihua Sun, Tariq Khan, Shuquan Zhang, Sangen Zhao, Junhua LuoAbstract:Tri-n-butylammonium Trichloroacetate (TBAT), a novel hybrid material, undergoes a reversible phase transition around 196 K, which is triggered by torsion in the cations and the order–disorder transformations of both ions.
