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Christoph Janiak - One of the best experts on this subject based on the ideXlab platform.
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Hydrogen-bonded supramolecular metal-imidazolate frameworks: gas sorption, Magnetic and UV/Vis spectroscopic properties
Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2019Co-Authors: Anas Alrefai, Suvendu Sekhar Mondal, Alexander Wruck, Philipp Brandt, Sophie Schönfeld, Birgit Weber, Alexandra Kelling, Uwe Schilde, Christoph Janiak, Lawrence RybakowskiAbstract:By varying reaction parameters for the syntheses of the hydrogen-bonded metal-imidazolate frameworks (HIF) HIF-1 and HIF-2 (featuring 14 Zn and 14 Co atoms, respectively) to increase their yields and crystallinity, we found that HIF-1 is generated in two different frameworks, named as HIF-1a and HIF-1b. HIF-1b is isostructural to HIF-2. We determined the gas sorption and Magnetic properties of HIF-2. In comparison to HIF-1a (Brunauer–Emmett–Teller (BET) surface area of 471 m2 g−1), HIF-2 possesses overall very low gas sorption uptake capacities [BET(CO2) surface area = 85 m2 g−1]. Variable temperature Magnetic Susceptibility Measurement of HIF-2 showed antiferroMagnetic exchange interactions between the cobalt(II) high-spin centres at lower temperature. Theoretical analysis by density functional theory confirmed this finding. The UV/Vis-reflection spectra of HIF-1 (mixture of HIF-1a and b), HIF-2 and HIF-3 (with 14 Cd atoms) were measured and showed a characteristic absorption band centered at 340 nm, which was indicative for differences in the imidazolate framework.
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Magnetic and luminescence properties of cu ii cu ii 4o4 core and cd ii mixed ligand metal organic frameworks constructed from 1 2 bis 1 2 4 triazol 4 yl ethane and benzene 1 3 5 tricarboxylate
Inorganica Chimica Acta, 2009Co-Authors: Hesham A Habib, Joaquin Sanchiz, Christoph JaniakAbstract:The hydrothermal reaction of Cu(NO 3 ) 2 · 3H 2 O, Cu(ClO 4 ) 2 · 6H 2 O, or CdSO 4 · 8/3H 2 O with benzene-1,3,5-tricarboxylic acid (H 3 btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers and networks (MOFs) 1 ∞ 1 ∞ {[Cu(H 2 btc) 2 (μ-btre)]} ( 1 ), 3 ∞ 3 ∞ {[Cu 4 (μ 5 -btc) 2 (μ 3 -OH) 2 (μ 4 -btre)] · 2H 2 O} ( 2 ), and 3 ∞ 3 ∞ {[Cd 3 (μ 6 -btc) 2 (μ 4 -btre)] · H 2 O} ( 3 ). The centrosymmetric tetranuclear, chair-shaped or stepped-cubane Cu 4 O 4 metal building unit in 2 has three different Cu contacts, each involving more than one bridging group. A quasi-butterfly magnetostructural model shows dominant antiferroMagnetic interactions in this Cu 4 unit with three different Magnetic exchange pathways with 2 J 1 = 258, 2J 2 = −416, and 2 J 3 = 484 cm −1 from the Magnetic Susceptibility Measurement between 1.9 and 300 K. For this Cu 4 O 4 unit the Eigenvalues associated with the zero field spin Hamiltonian were calculated by solving the 16 × 16 matrix in order to obtain here the numerical expression for the Magnetic Susceptibility. The cadmium-btre framework 3 , with bridged Cd strands, shows a strong bluish fluorescence at 421 nm upon excitation at 317 nm (not seen in the free btre ligand).
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mixed ligand coordination polymers from 1 2 bis 1 2 4 triazol 4 yl ethane and benzene 1 3 5 tricarboxylate trinuclear nickel or zinc secondary building units for three dimensional networks with crystal to crystal transformation upon dehydration
Dalton Transactions, 2008Co-Authors: Hesham A Habib, Joaquin Sanchiz, Christoph JaniakAbstract:The hydrothermal reaction of M(NO3)2·6H2O (M = Ni and Zn) with benzene-1,3,5-tricarboxylic acid (H3btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers (MOFs) 3∞{[Ni3(µ3-btc)2(µ4-btre)2(µ-H2O)2]·∼22H2O} (1) and 3∞{[Zn3(µ4-btc)2(µ4-btre)(H2O)2]·2H2O} (3). The compounds, characterized by single-crystal X-ray diffraction, X-ray powder diffraction and thermoanalysis feature trinuclear secondary building units (SBU) within the three-dimensional frameworks. The trinuclear nickel unit in 1 exhibits an intra-trimer together with some weak inter-trimer antiferroMagnetic coupling with J = −13.88(8) cm−1 from the Magnetic Susceptibility Measurement between 1.9–300 K. The zinc coordination polymer 3 shows a strong fluorescence at 423 nm upon excitation at 323 nm (not seen in the free btre ligand). Compound 3 is thermally robust until 200 °C (ambient pressure) where loss of the water molecules starts. Careful control of the dehydration procedure (freeze-drying) for 1 and (heating to 280 °C) for 3 allowed for a solid-state reaction with single-crystal-to-single-crystal structural transformations in obtaining the largely dehydrated products 3∞{[Ni3(µ2-btc)2(µ4-btre)2(µ-H2O)2(H2O)2]·4H2O} (2) and 3∞{[Zn3(µ6-btc)2(µ4-btre)2]·∼0.67H2O} (4), respectively. In the transformation from 1 to 2 the unit cell volume is reduced to about 60%. The transition from 3 to 4 involves breakage and formation of new Zn–O bonds.
Hesham A Habib - One of the best experts on this subject based on the ideXlab platform.
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Magnetic and luminescence properties of cu ii cu ii 4o4 core and cd ii mixed ligand metal organic frameworks constructed from 1 2 bis 1 2 4 triazol 4 yl ethane and benzene 1 3 5 tricarboxylate
Inorganica Chimica Acta, 2009Co-Authors: Hesham A Habib, Joaquin Sanchiz, Christoph JaniakAbstract:The hydrothermal reaction of Cu(NO 3 ) 2 · 3H 2 O, Cu(ClO 4 ) 2 · 6H 2 O, or CdSO 4 · 8/3H 2 O with benzene-1,3,5-tricarboxylic acid (H 3 btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers and networks (MOFs) 1 ∞ 1 ∞ {[Cu(H 2 btc) 2 (μ-btre)]} ( 1 ), 3 ∞ 3 ∞ {[Cu 4 (μ 5 -btc) 2 (μ 3 -OH) 2 (μ 4 -btre)] · 2H 2 O} ( 2 ), and 3 ∞ 3 ∞ {[Cd 3 (μ 6 -btc) 2 (μ 4 -btre)] · H 2 O} ( 3 ). The centrosymmetric tetranuclear, chair-shaped or stepped-cubane Cu 4 O 4 metal building unit in 2 has three different Cu contacts, each involving more than one bridging group. A quasi-butterfly magnetostructural model shows dominant antiferroMagnetic interactions in this Cu 4 unit with three different Magnetic exchange pathways with 2 J 1 = 258, 2J 2 = −416, and 2 J 3 = 484 cm −1 from the Magnetic Susceptibility Measurement between 1.9 and 300 K. For this Cu 4 O 4 unit the Eigenvalues associated with the zero field spin Hamiltonian were calculated by solving the 16 × 16 matrix in order to obtain here the numerical expression for the Magnetic Susceptibility. The cadmium-btre framework 3 , with bridged Cd strands, shows a strong bluish fluorescence at 421 nm upon excitation at 317 nm (not seen in the free btre ligand).
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mixed ligand coordination polymers from 1 2 bis 1 2 4 triazol 4 yl ethane and benzene 1 3 5 tricarboxylate trinuclear nickel or zinc secondary building units for three dimensional networks with crystal to crystal transformation upon dehydration
Dalton Transactions, 2008Co-Authors: Hesham A Habib, Joaquin Sanchiz, Christoph JaniakAbstract:The hydrothermal reaction of M(NO3)2·6H2O (M = Ni and Zn) with benzene-1,3,5-tricarboxylic acid (H3btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers (MOFs) 3∞{[Ni3(µ3-btc)2(µ4-btre)2(µ-H2O)2]·∼22H2O} (1) and 3∞{[Zn3(µ4-btc)2(µ4-btre)(H2O)2]·2H2O} (3). The compounds, characterized by single-crystal X-ray diffraction, X-ray powder diffraction and thermoanalysis feature trinuclear secondary building units (SBU) within the three-dimensional frameworks. The trinuclear nickel unit in 1 exhibits an intra-trimer together with some weak inter-trimer antiferroMagnetic coupling with J = −13.88(8) cm−1 from the Magnetic Susceptibility Measurement between 1.9–300 K. The zinc coordination polymer 3 shows a strong fluorescence at 423 nm upon excitation at 323 nm (not seen in the free btre ligand). Compound 3 is thermally robust until 200 °C (ambient pressure) where loss of the water molecules starts. Careful control of the dehydration procedure (freeze-drying) for 1 and (heating to 280 °C) for 3 allowed for a solid-state reaction with single-crystal-to-single-crystal structural transformations in obtaining the largely dehydrated products 3∞{[Ni3(µ2-btc)2(µ4-btre)2(µ-H2O)2(H2O)2]·4H2O} (2) and 3∞{[Zn3(µ6-btc)2(µ4-btre)2]·∼0.67H2O} (4), respectively. In the transformation from 1 to 2 the unit cell volume is reduced to about 60%. The transition from 3 to 4 involves breakage and formation of new Zn–O bonds.
Hitoshi Watarai - One of the best experts on this subject based on the ideXlab platform.
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Magnetic Susceptibility Measurement of a microdroplet interface using a Magnetic circuit
Analyst, 2009Co-Authors: Shigeki Egami, Hitoshi WataraiAbstract:A conventional method to measure the Magnetic Susceptibility of a microdroplet in a glass capillary has been constructed by using a Magnetic circuit (2.82 T) with a high Magnetic field gradient (B(dB/dz) = 3900 T2/m). The magnetophoretic velocity of a toluene droplet with ferrocene dispersed in 1 M HCl aqueous solution including K3[Fe(III)(CN)6], Fe(III)Cl3 and cetyltrimethylammonium bromide (CTAB) was measured and the volume Magnetic Susceptibility of droplets was determined. From the dependence of the Magnetic Susceptibility on the radius of the droplets, the interfacial Magnetic Susceptibility of the droplets adsorbed by Prussian blue aggregates was determined. The interfacial concentration of Prussian blue of individual droplet calculated from the observed Magnetic Susceptibility indicated that the interfacial concentration of Prussian blue are different even in similar sized droplets, suggesting inhomogeneous formation of interfacial aggregates.
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Magnetic Susceptibility Measurement of single iron cobalt carbonyl microcrystal by atmospheric magnetophoresis
Science and Technology of Advanced Materials, 2008Co-Authors: Masayori Suwa, Hitoshi Watarai, Yuichiro Oshino, Hiroshi Morita, Anzu Kasai, Jan SubrtAbstract:In this study, the use of an innovative atmospheric magnetophoresis, which enables us to measure the mass Magnetic Susceptibility and mass of a microparticle simultaneously, was demonstrated. Using this technique, we determined the Magnetic Susceptibility of a crystalline deposit of iron/cobalt carbonyl, mainly composed of Fe2(CO)9, which was prepared photochemically from a gaseous mixture of iron pentacarbonyl (Fe(CO)5) and cobalt tricarbonyl nitrosyl (Co(CO)3NO). The mass Magnetic Susceptibility and the characteristic relaxation time of the microcrystal were (7.0±1.9)×10−9 m3 kg−1 and (5.6±2.2)×10−4 s, respectively. The observed Magnetic Susceptibility shows that the microparticle was paraMagnetic. Assuming that the density was equal to that of Fe2(CO)9 (2.1×103 kg m−3) and that the shape of the particle was spherical, a hydrodynamic radius of 4.7 μm and a mass of 0.91 ng were observed. It was suggested that Co was incorporated in Fe2(CO)9.
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Magnetic Susceptibility Measurement of single iron/cobalt carbonyl microcrystal by atmospheric magnetophoresis
Science and Technology of Advanced Materials, 2008Co-Authors: Masayori Suwa, Hitoshi Watarai, Yuichiro Oshino, Hiroshi Morita, Anzu Kasai, Jan SubrtAbstract:In this study, the use of an innovative atmospheric magnetophoresis, which enables us to measure the mass Magnetic Susceptibility and mass of a microparticle simultaneously, was demonstrated. Using this technique, we determined the Magnetic Susceptibility of a crystalline deposit of iron/cobalt carbonyl, mainly composed of Fe2(CO)9, which was prepared photochemically from a gaseous mixture of iron pentacarbonyl (Fe(CO)5) and cobalt tricarbonyl nitrosyl (Co(CO)3NO). The mass Magnetic Susceptibility and the characteristic relaxation time of the microcrystal were (7.0±1.9)×10−9 m3 kg−1 and (5.6±2.2)×10−4 s, respectively. The observed Magnetic Susceptibility shows that the microparticle was paraMagnetic. Assuming that the density was equal to that of Fe2(CO)9 (2.1×103 kg m−3) and that the shape of the particle was spherical, a hydrodynamic radius of 4.7 μm and a mass of 0.91 ng were observed. It was suggested that Co was incorporated in Fe2(CO)9.
Jan Subrt - One of the best experts on this subject based on the ideXlab platform.
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Magnetic Susceptibility Measurement of single iron cobalt carbonyl microcrystal by atmospheric magnetophoresis
Science and Technology of Advanced Materials, 2008Co-Authors: Masayori Suwa, Hitoshi Watarai, Yuichiro Oshino, Hiroshi Morita, Anzu Kasai, Jan SubrtAbstract:In this study, the use of an innovative atmospheric magnetophoresis, which enables us to measure the mass Magnetic Susceptibility and mass of a microparticle simultaneously, was demonstrated. Using this technique, we determined the Magnetic Susceptibility of a crystalline deposit of iron/cobalt carbonyl, mainly composed of Fe2(CO)9, which was prepared photochemically from a gaseous mixture of iron pentacarbonyl (Fe(CO)5) and cobalt tricarbonyl nitrosyl (Co(CO)3NO). The mass Magnetic Susceptibility and the characteristic relaxation time of the microcrystal were (7.0±1.9)×10−9 m3 kg−1 and (5.6±2.2)×10−4 s, respectively. The observed Magnetic Susceptibility shows that the microparticle was paraMagnetic. Assuming that the density was equal to that of Fe2(CO)9 (2.1×103 kg m−3) and that the shape of the particle was spherical, a hydrodynamic radius of 4.7 μm and a mass of 0.91 ng were observed. It was suggested that Co was incorporated in Fe2(CO)9.
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Magnetic Susceptibility Measurement of single iron/cobalt carbonyl microcrystal by atmospheric magnetophoresis
Science and Technology of Advanced Materials, 2008Co-Authors: Masayori Suwa, Hitoshi Watarai, Yuichiro Oshino, Hiroshi Morita, Anzu Kasai, Jan SubrtAbstract:In this study, the use of an innovative atmospheric magnetophoresis, which enables us to measure the mass Magnetic Susceptibility and mass of a microparticle simultaneously, was demonstrated. Using this technique, we determined the Magnetic Susceptibility of a crystalline deposit of iron/cobalt carbonyl, mainly composed of Fe2(CO)9, which was prepared photochemically from a gaseous mixture of iron pentacarbonyl (Fe(CO)5) and cobalt tricarbonyl nitrosyl (Co(CO)3NO). The mass Magnetic Susceptibility and the characteristic relaxation time of the microcrystal were (7.0±1.9)×10−9 m3 kg−1 and (5.6±2.2)×10−4 s, respectively. The observed Magnetic Susceptibility shows that the microparticle was paraMagnetic. Assuming that the density was equal to that of Fe2(CO)9 (2.1×103 kg m−3) and that the shape of the particle was spherical, a hydrodynamic radius of 4.7 μm and a mass of 0.91 ng were observed. It was suggested that Co was incorporated in Fe2(CO)9.
Joaquin Sanchiz - One of the best experts on this subject based on the ideXlab platform.
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Magnetic and luminescence properties of cu ii cu ii 4o4 core and cd ii mixed ligand metal organic frameworks constructed from 1 2 bis 1 2 4 triazol 4 yl ethane and benzene 1 3 5 tricarboxylate
Inorganica Chimica Acta, 2009Co-Authors: Hesham A Habib, Joaquin Sanchiz, Christoph JaniakAbstract:The hydrothermal reaction of Cu(NO 3 ) 2 · 3H 2 O, Cu(ClO 4 ) 2 · 6H 2 O, or CdSO 4 · 8/3H 2 O with benzene-1,3,5-tricarboxylic acid (H 3 btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers and networks (MOFs) 1 ∞ 1 ∞ {[Cu(H 2 btc) 2 (μ-btre)]} ( 1 ), 3 ∞ 3 ∞ {[Cu 4 (μ 5 -btc) 2 (μ 3 -OH) 2 (μ 4 -btre)] · 2H 2 O} ( 2 ), and 3 ∞ 3 ∞ {[Cd 3 (μ 6 -btc) 2 (μ 4 -btre)] · H 2 O} ( 3 ). The centrosymmetric tetranuclear, chair-shaped or stepped-cubane Cu 4 O 4 metal building unit in 2 has three different Cu contacts, each involving more than one bridging group. A quasi-butterfly magnetostructural model shows dominant antiferroMagnetic interactions in this Cu 4 unit with three different Magnetic exchange pathways with 2 J 1 = 258, 2J 2 = −416, and 2 J 3 = 484 cm −1 from the Magnetic Susceptibility Measurement between 1.9 and 300 K. For this Cu 4 O 4 unit the Eigenvalues associated with the zero field spin Hamiltonian were calculated by solving the 16 × 16 matrix in order to obtain here the numerical expression for the Magnetic Susceptibility. The cadmium-btre framework 3 , with bridged Cd strands, shows a strong bluish fluorescence at 421 nm upon excitation at 317 nm (not seen in the free btre ligand).
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mixed ligand coordination polymers from 1 2 bis 1 2 4 triazol 4 yl ethane and benzene 1 3 5 tricarboxylate trinuclear nickel or zinc secondary building units for three dimensional networks with crystal to crystal transformation upon dehydration
Dalton Transactions, 2008Co-Authors: Hesham A Habib, Joaquin Sanchiz, Christoph JaniakAbstract:The hydrothermal reaction of M(NO3)2·6H2O (M = Ni and Zn) with benzene-1,3,5-tricarboxylic acid (H3btc) and 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) produced the mixed-ligand coordination polymers (MOFs) 3∞{[Ni3(µ3-btc)2(µ4-btre)2(µ-H2O)2]·∼22H2O} (1) and 3∞{[Zn3(µ4-btc)2(µ4-btre)(H2O)2]·2H2O} (3). The compounds, characterized by single-crystal X-ray diffraction, X-ray powder diffraction and thermoanalysis feature trinuclear secondary building units (SBU) within the three-dimensional frameworks. The trinuclear nickel unit in 1 exhibits an intra-trimer together with some weak inter-trimer antiferroMagnetic coupling with J = −13.88(8) cm−1 from the Magnetic Susceptibility Measurement between 1.9–300 K. The zinc coordination polymer 3 shows a strong fluorescence at 423 nm upon excitation at 323 nm (not seen in the free btre ligand). Compound 3 is thermally robust until 200 °C (ambient pressure) where loss of the water molecules starts. Careful control of the dehydration procedure (freeze-drying) for 1 and (heating to 280 °C) for 3 allowed for a solid-state reaction with single-crystal-to-single-crystal structural transformations in obtaining the largely dehydrated products 3∞{[Ni3(µ2-btc)2(µ4-btre)2(µ-H2O)2(H2O)2]·4H2O} (2) and 3∞{[Zn3(µ6-btc)2(µ4-btre)2]·∼0.67H2O} (4), respectively. In the transformation from 1 to 2 the unit cell volume is reduced to about 60%. The transition from 3 to 4 involves breakage and formation of new Zn–O bonds.