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A peptide-based metal-organic framework (MOF), a metal peptide framework (MPF), constructed from an oligovaline peptide family is described. The MPFs are stable and have some internal porosity, which has made them a promising prototype for the further development of MPFs.

Research has been conducted on the transition metal complexes, terpy-nitrony-nitroxide and terpy-imino-nitroxide. The preparation of these complexes has been carried out and the results are reported.

Two new one-dimensional nickel(II) complexes were synthesized and characterized. The two complexes are similar and may be described as one-dimensional with double-azido-bridged ligands in end-to-end and end-on coordination alternatively, while the end-on moiety is almost identical for the two complexes, the end-to-end moiety is different in each structure.

The photochemical formation of ferrimagnetic chains from a pair of manganese complexes a and b of bis(hexafluoroacetylacetonato)manganese(II) coordinated with diazodi(4-pyridyl)methane in the cis and trans arrangements as repeating units was described. The two isomeric manganese derivatives were prepared individually and were found to have helical and zigzag chain structures. Irradiation of the dilute paramagnetic manganese complexes transformed the diazo groups to the triplet carbenes and formed extended ferrimagnetic chains containing photochemically generated 2p spins.

Diazodi-4-pyridylmethane, a new bridging ligand, has been prepared, with two functional groups, two pyridyl nitrogens and a diazo group. The crystal structure and magnetic properties of copper complex where interaction between the Cu(II) ion and the generated carbene was found to be ferromagnetic is reported. Temperature dependence of the magnetic susceptibility and magnetic interaction in a 1:2 complex of Cu(hfac)2 with diazophenyl-4-pyridylmethane was also considered.

Transmetalation (Ni/Pt system), C(sub enolate)-metal bond formation (Pd/Au system) or O(sub enolate)-metal bond formation (Ni/Co system) may occur between nickel- or palladium-coordinated phosphino enolate ligands and metal electrophiles. This was gleaned from an investigation of the reactions of phosphino enolates toward electrophilic metal reagents. The crystal structures of Pd-Au and Ni-Co complexes, which reveal a different chemoselectivity of the enolate moiety, are described.

The transition metal coordination compounds are prepared from 1,9-bis(3,5-dimethyl-1-pyrazolyl)-3,7-dithia-5-nonanol (Hbdnol), which acts as a pentadentate ligand. IR, ligand field spectroscopy and EPR reveal that Ni(bdnol)Cl3 exhibits ferromagnetic intramolecular interaction and an antiferromagnetic ordering between adjacent dimers. The dinculear copper complex are antiferromagnetically coupled and are EPR silent at room temperature. The syntheses of Co(bdnol)(NCS)3, Zn2(bdnol)Cl(NCS)2, Cu2(bdnol)(NO3)3 and Cu2(Hbdnol)(NCS)2 are discussed.

The synthesis and characterization of a new carboxylato-bridged [Co.sup.II]thiophenedicarboxylic acid (TDC) compound is presented. The title compound has shown an unprecedented asymmetric tetradentate coordination mode of the carboxylate functions and the magnetic measurements have shown weak ferromagnetic interactions between the Co ions within the dimers.

The structural and magnetic synthesis of a series of transition-metal molecular compounds resulting from the combination of 3-pyridine sulfonate-water heterocomplexation processes is reported. The overlap between magnetic orbitals of the complexes was modified at low temperature which influenced the spin polarization mechanism along the H-bonds resulting in different intermolecular magnetic interactions.

Density functional theory (DFT) based on hybrid functional and localized atomic type basis sets is employed for calculating the exchange couplings in the layered three-dimensional compound Cu2(OH)3NO3. The result helped in achieved a sound theoretical determination of a measurable quantity without resorting to any approximation on the nature and the range of magnetic interactions providing accurate values by considerably enriching the interpretation of the magnetic susceptibility.

Dehydration of the hybrid compound [Ni3(OH)2(tp)2(H2O)4] (1) upon heating led to the sequential removal of coordinated water molecules to give [Ni3(OHMtp)2(H2O)2] (2) at T1 = 433 K and thereafter anhydrous [Ni2(OH)2(tp)] (3) at T2 = 483 K. These two successive structural transformations were thoroughly characterized by powder X-ray diffraction assisted by density functional theory calculations. The crystal structures of the two new compounds 2 and 3 were determined. It was shown that at T1 (433 K) the infinite nickel oxide chains built of the repeating structural unit [Ni3(μ3-OH)2]4+ in 1 collapse and lead to infinite porous layers, forming compound 2. The second transformation at T2 (483 K) gave the expected anhydrous compound 3, which is isostructural with Co2(OH)2(tp). These irreversible transitions directly affect the magnetic behavior of each phase. Hence, 1 was found to be antiferromagnetic at TN = 4.11 K, with metamagnetic behavior wim a threshold field Hc of ca. 0.6 T. Compound 2 exhibits canted antiferromagnetism below TN = 3.19 K, and 3 is ferromagnetic below Tc = 4.5 K. [ABSTRACT FROM AUTHOR]

Single crystals of the layered copper hydroxide dodecylsulfate Cu2(OH)3(C12H25SO4) have been obtained for the first time, by controlled hydrolysis of an aqueous copper acetate solution. Interestingly, this compound crystallizes in a noncentrosymmetric space group (P21, a = 5.591(10) Å, b = 6.108(11) Å, c = 26.96(5) Å, α = γ = 90°, β = 92.76°), which is further confirmed by nonlinear optical measurements. Within the course of the synthesis, a probable intermediate between Cu(OAc)2•H2O and the layered Cu2(OH)3(C12H25SO4) was isolated and characterized. X-ray structure analysis showed that this intermediate presents a ribbon-like structure of formula Cu3(C12H25SO4)2(CH3COO)2(OH)2(H2O)2. The magnetic properties of the layered Cu2(OH)3(C12H25SO4) have been analyzed in the high-temperature region (T > 20 K) by considering a high-temperature series expansion for a S = 1/2 Heisenberg two-dimensional triangular lattice. At lower temperature, the compound shows a three-dimensional antiferromagnetic ordering (TN = 10.8 K). The ribbon-like compound Cu3(C12H25SO4)2(CH3COO)2(OH)2(H2O)2 presents an overall antiferromagnetic behavior, resulting from a combination of ferro- and antiferromagnetic interactions between nearest neighbors within the chains. [ABSTRACT FROM AUTHOR]

A new method of acidification and subsequent functionalization of the Aurivillius-phase Bi2SrTa2O9 (BST), using microwave irradiation, was developed. This method enables to obtain hybridized phases from layered BST. Functionalization of BST by various kinds of amines and diamines can be achieved in a few hours only, compared to much longer time (over a week) using conventional heating. Good crystallinity of the compounds is kept. In addition, a microwave-assisted preintercalation strategy was developed, allowing inserting new amines (bearing cyclic or aromatic groups) between the oxide layers previously unseen in this type of compound. This work opens new perspectives for the fast and easy functionalization of layered oxides with more elaborated molecules. [ABSTRACT FROM AUTHOR]

The reaction of nickel chloride with phenyl phosphonic acid under hydrothermal conditions resulted in the isolation of yellow-green single crystals of Ni[(C6H5PO3)(H2O). The structure of the compound has been solved by X-ray single-crystal diffraction studies. Ni[(C6H5PO3)(H2O)] crystallizes in the orthorhombic space group Pmn21 and is isostructural with the Mn(Il), Fe(ll), and Co(ll) analogues. It presents the typical features of the hybrid 2D structures, consisting of alternating inorganic and organic layers. The former are formed by six-coordinated nickel(ll) ions bridged by oxygen atoms into the layers. The inorganic layers are capped by the phenyl phosphonate groups, with phenyl groups of two adjacent ligands forming a hydrophobic bilayer region, and van der Waals contacts are established between them. The magnetic properties investigated by means of dc and ac susceptibility measurements point to an AF exchange coupling between nearest neighboring Ni(ll) ions. Below 5 K, the compound orders magnetically showing the typical features of a canted antiferromagnet. The magnetic behavior and magnetic dimensionality of Ni[(C6H5PO3)(H2O)] have been fully analyzed and compared to those of the Ni(II) parent compounds Ni[(RPO3)(H2O)] (where R = CH3, C18H37), which exhibit different symmetries of the inorganic layers and lengths of the R groups. [ABSTRACT FROM AUTHOR]

A new strategy for the functionalization of layered perovskites is presented, based on the in situ post-synthesis modification of a prefunctionalized phase by copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC). The microwave-assisted protonation and grafting of an alkyne alcohol provides the alkyne-functionalized precursor within a few hours, starting from Bi 2 SrTa 2 O 9 . The subsequent microwave-assisted in situ "click reaction" allows the post-synthesis modification of the precursor within ∼2 h, providing a layered perovskite functionalized by an alcohol-grafted 1,4-disubstituted-1H-1,2,3-triazole. Two compounds are described here, bearing an aliphatic and an aromatic substituent, which illustrates the general application of the method. This work opens new perspectives for the functionalization of layered perovskites, going beyond mere insertion/grafting reactions, and thus broadens the design possibilities and the range of applications of these hybrid systems.

A new method of acidification and subsequent functionalization of the Aurivillius-phase Bi2SrTa2O9 (BST), using microwave irradiation, was developed. This method enables to obtain hybridized phases from layered BST. Functionalization of BST by various kinds of amines and diamines can be achieved in a few hours only, compared to much longer time (over a week) using conventional heating. Good crystallinity of the compounds is kept. In addition, a microwave-assisted preintercalation strategy was developed, allowing inserting new amines (bearing cyclic or aromatic groups) between the oxide layers previously unseen in this type of compound. This work opens new perspectives for the fast and easy functionalization of layered oxides with more elaborated molecules.

Energy transport in organic materials is dependent on the coherent migration of optically induced excited states. For instance, in active organic waveguides, the tight packing of dye molecules allows delocalization of excitons over a distance generally limited to at most several hundred nanometers. Here, we demonstrate an alternative mechanism of energy transport in a triarylamine-based supramolecular organic waveguide that is plasmonic in nature and results in coherent energy propagation superior to 10 μm. The optical, electric, and magnetic properties of the doped material support the presence of metallic electrons that couple with and transport incident light. These results show that organic metals constitute a novel class of materials with efficient energy transport and are of potential interest for optoelectronics, plasmonics, and artificial light-energy harvesting systems.

The reaction of Na10[α-SiW9O34] with tetravalent metallic cations such as 4f ((NH4)2Ce(NO3)6), 5d (HfCl4), or 5f (UCl4 and Th(NO3)4) in a pH 4.7 sodium acetate buffer solution leads to the formation of four sandwich-type polyoxometalates [Ce4(μ(3)-O)2(SiW9O34)2(CH3COO)2](10-) (1), [U4(μ(3)-O)2(SiW9O34)2(CH3COO)2](10-) (2), [Th3(μ(3)-O)(μ(2)-OH)3(SiW9O34)2](13-) (3), and [Hf3(μ(2)-OH)3(SiW9O34)2](11-) (4). All four compounds consist of a polynuclear cluster fragment stabilized by two [α-SiW9O34](10-) polyanions. Compounds 1 and 2 are isostructural with a tetranuclear core (Ce4, U4), while compound 3 presents a trinuclear Th3 core bearing a μ(3)-O-centered bridge. It is an unprecedented configuration in the case of the thorium(IV) cluster. Compound 4 also possesses a trinuclear Hf3 core but with the absence of the μ(3)-O bridge. The molecules have been characterized by single-crystal X-ray diffraction, (183)W and (29)Si nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) analysis.

Dehydration of the hybrid compound [Ni3(OH)2(tp)2(H2O)4] (1) upon heating led to the sequential removal of coordinated water molecules to give [Ni3(OH)2(tp)2(H2O)2] (2) at T1 = 433 K and thereafter anhydrous [Ni2(OH)2(tp)] (3) at T2 = 483 K. These two successive structural transformations were thoroughly characterized by powder X-ray diffraction assisted by density functional theory calculations. The crystal structures of the two new compounds 2 and 3 were determined. It was shown that at T1 (433 K) the infinite nickel oxide chains built of the repeating structural unit [Ni3(μ3-OH)2](4+) in 1 collapse and lead to infinite porous layers, forming compound 2. The second transformation at T2 (483 K) gave the expected anhydrous compound 3, which is isostructural with Co2(OH)2(tp). These irreversible transitions directly affect the magnetic behavior of each phase. Hence, 1 was found to be antiferromagnetic at TN = 4.11 K, with metamagnetic behavior with a threshold field Hc of ca. 0.6 T. Compound 2 exhibits canted antiferromagnetism below TN = 3.19 K, and 3 is ferromagnetic below TC = 4.5 K.

By controlling the water content, a new poly-oxo-metalate species containing 38 uranium centers has been solvothermally synthesized in the presence of benzoic acid in tetrahydrofuran (THF). The {U38} motif contains a distorted UO2 core of fluorite type, stabilized by benzoate and THF molecules. This compound is analogous to the {Pu38} motif and was characterized by X-ray photoelectron spectroscopy and magnetic analyses.

Polyelectrolyte multilayer (PEM) films have become very popular for surface functionalization and the design of functional architectures such as hollow polyelectrolyte capsules. It is known that properties such as permeability to small ionic solutes are strongly dependent on the buildup regime of the PEM films. This permeability can be modified by tuning the ionization degree of the polycations or polyanions, provided the film is made from weak polyelectrolytes. In most previous investigations, this was achieved by playing on the solution pH either during the film buildup or by a postbuildup pH modification. Herein we investigate the functionalization of poly(allylamine hydrochloride)/poly(glutamic acid) (PAH/PGA) multilayers by ferrocyanide and Prussian Blue (PB). We demonstrate that dynamic exchange processes between the film and polyelectrolyte solutions containing one of the component polyelectrolyte allow one to modify its Donnan potential and, as a consequence, the amount of ferrocyanide anions able to be retained in the PAH/PGA film. This ability of the film to be a tunable reservoir of ferrocyanide anions is then used to produce a composite film containing PB particles obtained by a single precipitation reaction with a solution containing Fe(3+) cations in contact with the film. The presence of PB in the PEM films then provides magnetic as well as electrochemical properties to the whole architecture.