The Missing Link: Synthesis, Crystal Structure, and Thermogravimetric Studies of InPO₄·H₂O

A new binary indium phosphate monohydrate, InPO4·H2O, was synthesized under hydrothermal conditions. Its crystal structure was determined using single-crystal X-ray diffraction methods. InPO4·H2O crystallizes in the triclinic system, space group P1̄, with a = 5.4342(6) Å, b = 5.5508(4) Å, c = 6.5446(5) Å, α = 97.593(6)°, β = 94.558(6)°, γ = 107.565(6)°, and Z = 2. The 3-D framework is built from (In2O8(OH2)2) dimers connected through (PO4) tetrahedra. Water molecules directly bond to indium. Thermogravimetric studies indicate that InPO4·H2O loses one water molecule in the temperature range between 370 and 480 °C to yield the previously reported anhydrous InPO4. The loss of water corresponds to condensation of the (In2O8(OH2)2) dimers into linear chains of edge-sharing (InO6) octahedra. InPO4·H2O represents the missing link between InPO4 and InPO4·2H2O. The structural relationships between InPO4·2H2O, InPO4·H2O, InPO4, and other MIII(PO4)·2H2O are discussed

AVNb₃Cl₁₁ (A = K, Rb, Cs, Tl): A Series of Layered Vanadium Niobium Halides Based on Triangular Nb₃ Clusters

The first quaternary vanadium niobium compounds containing triangular Nb3 clusters corresponding to the general formula, AVNb3Cl11 (A = K, Rb, Cs, Tl), have been prepared in sealed quartz tubes from stoichiometric amounts of ACl (A = K, Rb, Cs), or Tl metal, VCl3, Nb powder, and NbCl5 heated at 740 °C. The compounds crystallize in the orthorhombic space group Pnma (No. 62). The crystal structures of the Rb and Tl members were determined by single-crystal X-ray diffraction techniques. Crystal data:  a = 12.771(3) Å, b = 6.811(2) Å, c = 17.183(3) Å, V = 1494.6(1) Å3, and Z = 4 for A = Rb; and a = 12.698(5) Å, b = 6.798(3) Å, c = 17.145(10) Å, V = 1480.0(13) Å3, and Z = 4 for A = Tl. The crystal structure of AVNb3Cl11 consists of triangular Nb3Cl13 clusters (Nb−Nb = 2.826 Å) connected to each other via four outer ligands to form infinite chains along the b-axis. The chains are connected by vanadium atoms located in an octahedral environment to form puckered sheets. The A+ counterions are located between adjacent sheets and coordinate to twelve chlorine ligands in anticubeoctahedral geometry. Electronic structure calculations show bonding orbitals similar to those in Nb3Cl8. Magnetic susceptibility measurements show paramagnetic Curie Weiss behavior

Superexpanded Prussian-Blue Analogue with [Fe(CN)₆]^4-, [Nb₆Cl₁₂(CN)₆]^4-, and [Mn(<i>salen</i>)]⁺ as Building Units

A cluster-based 3D cyano-bridged trimetallic porous coordination polymer, [H3O]2[Fe(CN)6(Mn(salen))6Nb6Cl12(CN)6]·3H2O (1) with a superexpanded Prussian-blue-type structure built of [Nb6Cl12(CN)6]4-, [Fe(CN)6]4-, and [Mn(salen)]+ building units was synthesized and characterized. 1 shows overall ferromagnetic coupling and has a surface area of 55.4 m2/g

Superexpanded Prussian-Blue Analogue with [Fe(CN)₆]^4-, [Nb₆Cl₁₂(CN)₆]^4-, and [Mn(<i>salen</i>)]⁺ as Building Units

A cluster-based 3D cyano-bridged trimetallic porous coordination polymer, [H3O]2[Fe(CN)6(Mn(salen))6Nb6Cl12(CN)6]·3H2O (1) with a superexpanded Prussian-blue-type structure built of [Nb6Cl12(CN)6]4-, [Fe(CN)6]4-, and [Mn(salen)]+ building units was synthesized and characterized. 1 shows overall ferromagnetic coupling and has a surface area of 55.4 m2/g

AVNb₃Cl₁₁ (A = K, Rb, Cs, Tl): A Series of Layered Vanadium Niobium Halides Based on Triangular Nb₃ Clusters

The first quaternary vanadium niobium compounds containing triangular Nb3 clusters corresponding to the general formula, AVNb3Cl11 (A = K, Rb, Cs, Tl), have been prepared in sealed quartz tubes from stoichiometric amounts of ACl (A = K, Rb, Cs), or Tl metal, VCl3, Nb powder, and NbCl5 heated at 740 °C. The compounds crystallize in the orthorhombic space group Pnma (No. 62). The crystal structures of the Rb and Tl members were determined by single-crystal X-ray diffraction techniques. Crystal data:  a = 12.771(3) Å, b = 6.811(2) Å, c = 17.183(3) Å, V = 1494.6(1) Å3, and Z = 4 for A = Rb; and a = 12.698(5) Å, b = 6.798(3) Å, c = 17.145(10) Å, V = 1480.0(13) Å3, and Z = 4 for A = Tl. The crystal structure of AVNb3Cl11 consists of triangular Nb3Cl13 clusters (Nb−Nb = 2.826 Å) connected to each other via four outer ligands to form infinite chains along the b-axis. The chains are connected by vanadium atoms located in an octahedral environment to form puckered sheets. The A+ counterions are located between adjacent sheets and coordinate to twelve chlorine ligands in anticubeoctahedral geometry. Electronic structure calculations show bonding orbitals similar to those in Nb3Cl8. Magnetic susceptibility measurements show paramagnetic Curie Weiss behavior

Supramolecular Assemblies Built of [Nb₆Cl₁₂(CN)₆]^4- Octahedral Metal Clusters and [Mn(<i>a</i><i>cacen</i>)]⁺ Complexes

Reactions between solutions of [Me4N]4[Nb6Cl12(CN)6]·2MeOH and [Mn(L)]Cl (L = acacen2- = bis(acetylacetonato)ethylenediamine at room temperature led to the formation of four compounds containing supramolecular assemblies formed of [Nb6Cl12(CN)6]4- and [Mn(L)]+ as building units. The four compounds were characterized by single-crystal X-ray diffraction, IR, elemental analysis, thermogravimetric analysis, and magnetic susceptibility measurements (for 3). In 1, each cluster is coordinated by one [Mn(L)(MeOH)]+ via a CN- ligand to give an anionic dimeric unit {[Mn(L)(MeOH)][Nb6Cl12(CN)6]}3-, which connect to each other via hydrogen bonding between the CN- ligand and MeOH from the cations [Mn(L)(MeOH)2]+ to give anionic tubular-like chains. The structure of 2 comprises trimeric units {[Mn(L)(H2O)]2[Nb6Cl12(CN)6]}2- in which each cluster is trans-coordinated by two [Mn(L)(H2O)]+ cations via the CN- ligand. The trimeric units are connected to each other via hydrogen bonding between CN- and the water of coordination to give anionic chains along the crystallographic a axis. The chains are connected to each other through further hydrogen bonding to give an overall three-dimensional hydrogen-bonded framework. In 3, each cluster is coordinated by two [Mn(L)(MeCN)]+ and two [Mn(L)(H2O)]+ via CN- ligand to give neutral pentameric units that are connected through hydrogen bonding between CN- and aqua ligands to give hydrogen-bonded chains along the crystallographic b axis. 4 is based on two supramolecular ions; the cation consists of a heptameric unit {[Mn(L)(H2O)]4[Mn(L)]2[Nb6Cl12(CN)6]}2+ in which each cluster is coordinated by six [Mn(L)]+ via CN- ligand, whereas the anion {[Mn(L)]2[Nb6Cl12(CN)6]}2- is the same as that found in 2. Electrostatic interactions and hydrogen bonding between these two supramolecular species afford a 1D framework. Magnetic susceptibility shows that 3 is paramagnetic with four high-spin Mn(III) ions. Thermal behaviors of 1−4 are presented

Supramolecular Assemblies Built of [Nb₆Cl₁₂(CN)₆]^4- Octahedral Metal Clusters and [Mn(<i>a</i><i>cacen</i>)]⁺ Complexes

Reactions between solutions of [Me4N]4[Nb6Cl12(CN)6]·2MeOH and [Mn(L)]Cl (L = acacen2- = bis(acetylacetonato)ethylenediamine at room temperature led to the formation of four compounds containing supramolecular assemblies formed of [Nb6Cl12(CN)6]4- and [Mn(L)]+ as building units. The four compounds were characterized by single-crystal X-ray diffraction, IR, elemental analysis, thermogravimetric analysis, and magnetic susceptibility measurements (for 3). In 1, each cluster is coordinated by one [Mn(L)(MeOH)]+ via a CN- ligand to give an anionic dimeric unit {[Mn(L)(MeOH)][Nb6Cl12(CN)6]}3-, which connect to each other via hydrogen bonding between the CN- ligand and MeOH from the cations [Mn(L)(MeOH)2]+ to give anionic tubular-like chains. The structure of 2 comprises trimeric units {[Mn(L)(H2O)]2[Nb6Cl12(CN)6]}2- in which each cluster is trans-coordinated by two [Mn(L)(H2O)]+ cations via the CN- ligand. The trimeric units are connected to each other via hydrogen bonding between CN- and the water of coordination to give anionic chains along the crystallographic a axis. The chains are connected to each other through further hydrogen bonding to give an overall three-dimensional hydrogen-bonded framework. In 3, each cluster is coordinated by two [Mn(L)(MeCN)]+ and two [Mn(L)(H2O)]+ via CN- ligand to give neutral pentameric units that are connected through hydrogen bonding between CN- and aqua ligands to give hydrogen-bonded chains along the crystallographic b axis. 4 is based on two supramolecular ions; the cation consists of a heptameric unit {[Mn(L)(H2O)]4[Mn(L)]2[Nb6Cl12(CN)6]}2+ in which each cluster is coordinated by six [Mn(L)]+ via CN- ligand, whereas the anion {[Mn(L)]2[Nb6Cl12(CN)6]}2- is the same as that found in 2. Electrostatic interactions and hydrogen bonding between these two supramolecular species afford a 1D framework. Magnetic susceptibility shows that 3 is paramagnetic with four high-spin Mn(III) ions. Thermal behaviors of 1−4 are presented

Assembly of Hybrid Inorganic−Organic Materials from Octahedral Nb₆ Clusters and Metal Complexes

The octahedral edge-bridged niobium cyano-chloride cluster [Nb6Cl12(CN)6]4- and the [Mn(salen)]+ metal complex have been used as building units to prepare solid-state materials with extended frameworks at room temperature through self-assembly processes. Three materials with different dimensionalities were prepared and characterized:  (Me4N)4[Nb6Cl12(CN)6]·2MeOH (1) (0D), (Me4N)2[Mn(salen)]2[Nb6Cl12(CN)6] (2) (2D), and (Et4N)2[Mn(salen)(MeOH)]2[Nb6Cl12(CN)6]·2MeOH (3) (1D). 1 was used as cluster precursor for the preparation of 2 and 3. The framework dimensionality seems to be affected by the size of the template-counterion used. Single-crystal X-ray analysis revealed that 1 is based on discrete [Nb6Cl12(CN)6]4- separated by (Me4N)+ and MeOH molecules. 2 has a two-dimensional framework, in which each layer is formed by [Nb6Cl12(CN)6]4- clusters connected through four cyanide ligands to four different [Mn(salen)]+. Each manganese complex connects two clusters through Nb−CN−Mn−NC−Nb bridges, leading to the formation of anionic layers interleaved by (Me4N)+. In 3, every cluster unit [Nb6Cl12(CN)6]4- is linked to two [Mn(salen)(MeOH)]+ units through two apical trans cyanide ligands, leading to the formation of trimeric units {Mn−(NC)[Nb6Cl12(CN)4](CN)−Mn}. Every trimeric unit connects to two neighboring units through hydrogen bonding between OMeOH from coordinated methanol ligand and NCN from two neighboring clusters, resulting in the formation of anionic chains along the crystallographic a axis {[Mn(salen)(MeOH)]2[(Nb6Cl12)(CN)6]}2-. The chains are separated by (Et4N)+ and MeOH. Magnetic properties and thermal behavior of these new hybrid inorganic−organic compounds are presented

Octahedral Niobium Chloride Clusters as Building Blocks of Templated Prussian Blue Framework Analogues

The preparation, structure, and magnetic properties of the first three-dimensional framework containing octahedral niobium cyanochloride clusters as building units are reported. Reactions of aqueous solutions of (Me4N)2K2[Nb6Cl12(CN)6] (2) with aqueous solutions of MnCl2 result in the precipitation of the compound (Me4N)2[MnNb6Cl12(CN)6] (3). The structure of 3 was determined from single-crystal X-ray diffraction study (crystal data:  cubic, Fm3̄m (No. 225), a = 15.513(4) Å, V = 3733.2(12) Å3, Z = 4). Its 3D framework is based on edge-bridged [Nb6Cl12]2+ clusters and Mn2+ ions bridged by cyanide ligands to form a cfc lattice [MnNb6Cl12(CN)6]2- in which all tetrahedral sites are occupied by the cations (Me4N)+ which act as charge compensating template. The structure of 3 can be considered as an expansion of the Prussian blue framework in which [Fe(CN)6]4- is replaced by the cluster [Nb6Cl12(CN)6]4-. Magnetic susceptibility measurements indicate that Mn2+ is present in a high spin d5 configuration. No magnetic ordering is observed

Octahedral Niobium Chloride Clusters as Building Blocks of Templated Prussian Blue Framework Analogues

The preparation, structure, and magnetic properties of the first three-dimensional framework containing octahedral niobium cyanochloride clusters as building units are reported. Reactions of aqueous solutions of (Me4N)2K2[Nb6Cl12(CN)6] (2) with aqueous solutions of MnCl2 result in the precipitation of the compound (Me4N)2[MnNb6Cl12(CN)6] (3). The structure of 3 was determined from single-crystal X-ray diffraction study (crystal data:  cubic, Fm3̄m (No. 225), a = 15.513(4) Å, V = 3733.2(12) Å3, Z = 4). Its 3D framework is based on edge-bridged [Nb6Cl12]2+ clusters and Mn2+ ions bridged by cyanide ligands to form a cfc lattice [MnNb6Cl12(CN)6]2- in which all tetrahedral sites are occupied by the cations (Me4N)+ which act as charge compensating template. The structure of 3 can be considered as an expansion of the Prussian blue framework in which [Fe(CN)6]4- is replaced by the cluster [Nb6Cl12(CN)6]4-. Magnetic susceptibility measurements indicate that Mn2+ is present in a high spin d5 configuration. No magnetic ordering is observed