Carboxylate-Free Manganese(II) Phosphonate Assemblies: Synthesis, Structure, and Magnetism

The reaction of manganese­(II) salts with organophosphonic acid [<i>t</i>-BuPO₃H₂ or cyclopentyl phosphonic acid (C₅H₉PO₃H₂)] in the presence of ancillary nitrogen ligands [1,10-phenanthroline (phen) or 2,6-bis­(pyrazol-3-yl)­pyridine (dpzpy)], afforded, depending on the stoichiometry of the reactants and the reaction conditions, dinuclear, trinuclear, and tetranuclear compounds, [Mn₂(<i>t</i>-BuPO₃H)₄(phen)₂]·2DMF (<b>1</b>), [Mn₃(C₅H₉PO₃)₂(phen)₆]­(ClO₄)₂·7CH₃OH (<b>2</b>), [Mn₃(<i>t</i>-BuPO₃)₂(dpzpy)₃]­(ClO₄)₂·H₂O (<b>3</b>), [Mn₄(<i>t</i>-BuPO₃)₂(<i>t</i>-BuPO₃H)₂(phen)₆(H₂O)₂]­(ClO₄)₂ (<b>4</b>), and [Mn₄(C₅H₉PO₃)₂(phen)₈(H₂O)₂]­(ClO₄)₄ (<b>5</b>). Magnetic studies on <b>1</b>, <b>2</b>, and <b>4</b> reveal that the phosphonate bridges mediate weak antiferromagnetic interactions between the Mn^II ions have also been carried out

Carboxylate-Free Manganese(II) Phosphonate Assemblies: Synthesis, Structure, and Magnetism

The reaction of manganese­(II) salts with organophosphonic acid [<i>t</i>-BuPO₃H₂ or cyclopentyl phosphonic acid (C₅H₉PO₃H₂)] in the presence of ancillary nitrogen ligands [1,10-phenanthroline (phen) or 2,6-bis­(pyrazol-3-yl)­pyridine (dpzpy)], afforded, depending on the stoichiometry of the reactants and the reaction conditions, dinuclear, trinuclear, and tetranuclear compounds, [Mn₂(<i>t</i>-BuPO₃H)₄(phen)₂]·2DMF (<b>1</b>), [Mn₃(C₅H₉PO₃)₂(phen)₆]­(ClO₄)₂·7CH₃OH (<b>2</b>), [Mn₃(<i>t</i>-BuPO₃)₂(dpzpy)₃]­(ClO₄)₂·H₂O (<b>3</b>), [Mn₄(<i>t</i>-BuPO₃)₂(<i>t</i>-BuPO₃H)₂(phen)₆(H₂O)₂]­(ClO₄)₂ (<b>4</b>), and [Mn₄(C₅H₉PO₃)₂(phen)₈(H₂O)₂]­(ClO₄)₄ (<b>5</b>). Magnetic studies on <b>1</b>, <b>2</b>, and <b>4</b> reveal that the phosphonate bridges mediate weak antiferromagnetic interactions between the Mn^II ions have also been carried out

New Structural Form of a Tetranuclear Lanthanide Hydroxo Cluster: Dy₄ Analogue Display Slow Magnetic Relaxation

A series of tetranuclear lanthanide (Ln = Tb, Dy, Ho) hydroxo clusters has been synthesized by reaction of LnCl₃·6H₂O (Ln = Tb (<b>1</b>), Dy (<b>2</b>), Ho (<b>3</b>)) with <i>o</i>-vanilin based schiff base ligand 2-(2,3 dihydroxpropyl imino methyl) 6-methoxy phenol (H₃L) in methanol and in the presence of triethylamine as base. The solid state structures of all the products were established by single crystal X-ray diffraction technique. Magnetism studies reveal that Dy₄ analogue exhibits slow magnetic relaxation at low temperatures

Two Isostructural Coordination Polymers Showing Diverse Magnetic Behaviors: Weak Coupling (Ni^II) and an Ordered Array of Single-Chain Magnets (Co^II)

Two isomorphic 3-D complexes with the formulas [M₃(TPTA) (OH)₂(H₂O)₄]_<i>n</i> (M = Ni for <b>1</b> and Co for <b>2</b>; H₄TPTA = [1,1′:4′,1″-terphenyl]-2′,3,3″,5′-tetracarboxylic acid) have been synthesized and magnetically characterized. Complexes <b>1</b> (Ni^II) and <b>2</b> (Co^II) have the same 1-D rod-shaped inorganic SBUs but exhibit significantly different magnetic properties. Complex <b>2</b>(Co^II) is a 3-D arrangement of a 1-D Co^II single-chain magnet (SCM), while complex <b>1</b>(Ni^II) exhibits weak coupling

Molecular [(Fe₃)–(Fe₃)] and [(Fe₄)–(Fe₄)] Coordination Cluster Pairs as Single or Composite Arrays

The synthesis of molecular cluster pairs is a challenge for coordination chemists due to the potential applications of these species in molecular spintronics or quantum computing. The ligand H₄L, 1,3-bis-(3-oxo-3-(2-hydroxyphenyl)-propionyl)-2-methoxybenzene, has been successfully used to obtain a series of such complexes using the basic Fe­(III) trinuclear carboxylates as starting materials. Synthetic control has allowed the isolation of the two molecular cluster pairs that form the composite [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂[Fe₃O­(PhCO₂)₅(py)­(H₂L)]₂ (<b>1</b>). The dimers of trinuclear units, [Fe₃O­(PhCO₂)₅(H₂O)­(H₂L)]₂ (<b>2</b>) and [Fe₃O­(<i>o</i>-MePhCO₂)₅(H₂L)­(py)]₂ (<b>3</b>), and the dimers of tetranuclear units, [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂ (<b>4</b>) and [Fe₄O₂(<i>o</i>–MePhCO₂)₆(H₂L)­(pz)]₂ (<b>5</b>), are presented here. The magnetic properties of the reported aggregates show that they are pairs of semi-independent clusters weakly interacting magnetically as required for two-qubit quantum gates

Molecular [(Fe₃)–(Fe₃)] and [(Fe₄)–(Fe₄)] Coordination Cluster Pairs as Single or Composite Arrays

The synthesis of molecular cluster pairs is a challenge for coordination chemists due to the potential applications of these species in molecular spintronics or quantum computing. The ligand H₄L, 1,3-bis-(3-oxo-3-(2-hydroxyphenyl)-propionyl)-2-methoxybenzene, has been successfully used to obtain a series of such complexes using the basic Fe­(III) trinuclear carboxylates as starting materials. Synthetic control has allowed the isolation of the two molecular cluster pairs that form the composite [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂[Fe₃O­(PhCO₂)₅(py)­(H₂L)]₂ (<b>1</b>). The dimers of trinuclear units, [Fe₃O­(PhCO₂)₅(H₂O)­(H₂L)]₂ (<b>2</b>) and [Fe₃O­(<i>o</i>-MePhCO₂)₅(H₂L)­(py)]₂ (<b>3</b>), and the dimers of tetranuclear units, [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂ (<b>4</b>) and [Fe₄O₂(<i>o</i>–MePhCO₂)₆(H₂L)­(pz)]₂ (<b>5</b>), are presented here. The magnetic properties of the reported aggregates show that they are pairs of semi-independent clusters weakly interacting magnetically as required for two-qubit quantum gates

Molecular [(Fe₃)–(Fe₃)] and [(Fe₄)–(Fe₄)] Coordination Cluster Pairs as Single or Composite Arrays

The synthesis of molecular cluster pairs is a challenge for coordination chemists due to the potential applications of these species in molecular spintronics or quantum computing. The ligand H₄L, 1,3-bis-(3-oxo-3-(2-hydroxyphenyl)-propionyl)-2-methoxybenzene, has been successfully used to obtain a series of such complexes using the basic Fe­(III) trinuclear carboxylates as starting materials. Synthetic control has allowed the isolation of the two molecular cluster pairs that form the composite [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂[Fe₃O­(PhCO₂)₅(py)­(H₂L)]₂ (<b>1</b>). The dimers of trinuclear units, [Fe₃O­(PhCO₂)₅(H₂O)­(H₂L)]₂ (<b>2</b>) and [Fe₃O­(<i>o</i>-MePhCO₂)₅(H₂L)­(py)]₂ (<b>3</b>), and the dimers of tetranuclear units, [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂ (<b>4</b>) and [Fe₄O₂(<i>o</i>–MePhCO₂)₆(H₂L)­(pz)]₂ (<b>5</b>), are presented here. The magnetic properties of the reported aggregates show that they are pairs of semi-independent clusters weakly interacting magnetically as required for two-qubit quantum gates

Molecular [(Fe₃)–(Fe₃)] and [(Fe₄)–(Fe₄)] Coordination Cluster Pairs as Single or Composite Arrays

The synthesis of molecular cluster pairs is a challenge for coordination chemists due to the potential applications of these species in molecular spintronics or quantum computing. The ligand H₄L, 1,3-bis-(3-oxo-3-(2-hydroxyphenyl)-propionyl)-2-methoxybenzene, has been successfully used to obtain a series of such complexes using the basic Fe­(III) trinuclear carboxylates as starting materials. Synthetic control has allowed the isolation of the two molecular cluster pairs that form the composite [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂[Fe₃O­(PhCO₂)₅(py)­(H₂L)]₂ (<b>1</b>). The dimers of trinuclear units, [Fe₃O­(PhCO₂)₅(H₂O)­(H₂L)]₂ (<b>2</b>) and [Fe₃O­(<i>o</i>-MePhCO₂)₅(H₂L)­(py)]₂ (<b>3</b>), and the dimers of tetranuclear units, [Fe₄O₂(PhCO₂)₆(H₂L)­(pz)]₂ (<b>4</b>) and [Fe₄O₂(<i>o</i>–MePhCO₂)₆(H₂L)­(pz)]₂ (<b>5</b>), are presented here. The magnetic properties of the reported aggregates show that they are pairs of semi-independent clusters weakly interacting magnetically as required for two-qubit quantum gates

Two New Coordination Polymers with Co(II) and Mn(II): Selective Gas Adsorption and Magnetic Studies

A novel bifurcated ligand 3,5-di­(1<i>H</i>-benzo­[<i>d</i>]­imidazol-1-yl)­benzonitrile (DBIBN) has been synthesized, which reacts with Co­(II) and Mn­(II) salts to form new coordination polymers {[Co₂(DBIBA)₃]·Cl·9H₂O}_<i>n</i> (<b>1</b>) and {[Mn₃(DBIBA)₆]}_<i>n</i> (<b>2</b>), (DBIBA = 3,5-di­(1<i>H</i>-benzo­[d]­imidazol-1-yl)­benzoate), in which DBIBN get hydrolyzed into DBIBA under solvothermal conditions. Both the complexes have been characterized by single-crystal X-ray crystallography (XRD), IR spectroscopy, elemental analysis, thermogravimetry, and X-ray powder diffraction (PXRD). Complex <b>1</b> is a 3D coordination polymer composed of binuclear Co­(II) units, having (4,6) connected net. On the other hand, complex <b>2</b> is a layered structure with trinuclear Mn­(II) units, which has 4-connected 4⁴ <i><b>sql</b></i> topology. TGA and PXRD measurements show that the framework <b>1</b> is stable after desolvation. Desolvated framework <b>1</b> showed selective adsorption of CO₂ over N₂, H_2, and Ar. Variable temperature magnetic susceptibility measurements show that complex <b>1</b> exhibits weak antiferromagnetic behavior

Gas Adsorption, Magnetism, and Single-Crystal to Single-Crystal Transformation Studies of a Three-Dimensional Mn(II) Porous Coordination Polymer

A porous coordination polymer {[Mn₂(DBIBA)₃]­NO₃·3DMF­·4H₂O}_<i>n</i> (<b>1</b>) [DBIBAH = 3,5-di­(1<i>H</i>-benzo­[d]­imidazol-1-yl)­benzoic acid] has been synthesized solvothermally and structurally characterized by single-crystal X-ray diffraction. The following four new coordination polymers {[Mn₂(DBIBA)₃]­·ClO₄·DMF­·H₂O}_<i>n</i> (<b>2</b>), {[Mn₂(DBIBA)₃]­·Cl­·DMF­·8H₂O}_<i>n</i> (<b>3</b>), {[Mn₂(DBIBA)₃]­·NO₃­·CH₃OH­·5H₂O}_<i>n</i> (<b>4</b>) and {[Mn₂(DBIBA)₃]­·NO₃­·3CH₃COCH₃­·7H₂O}_<i>n</i> (<b>5</b>) have been synthesized from <b>1</b> via anion/solvent exchange protocols in a single-crystal to single-crystal fashion at room temperature. Gas sorption studies for desolvated compounds <b>1</b>, <b>2</b>, and <b>3</b> show that CO₂ uptake capacity is entirely dependent upon the size of the anion present in the framework. Complex <b>1</b> also exhibits antiferromagnetic properties below 17 K, confirmed through magnetic susceptibility measurements