Pius Adelani

Follower

Following

Public Views

Interests

Uploads

Papers by Pius Adelani

Heterobimetallic Copper(II) Uranyl Carboxyphenylphosphonates

Crystal Growth & Design, Sep 9, 2011

ABSTRACT

Hybrid Uranyl Arsonate Coordination Nanocages

Inorganic Chemistry, May 16, 2013

Nanoscopic uranyl coordination cages have been prepared by a facile route involving self-assembly... more Nanoscopic uranyl coordination cages have been prepared by a facile route involving self-assembly via temperature and solvent-driven, in situ ligand synthesis. The synthesis of hydrogen arsenate and pyroarsonate ligands in situ enhances flexibility, which is an important factor in producing these compounds.

Download

Metal-Controlled Assembly of Uranyl Diphosphonates toward the Design of Functional Uranyl Nanotubules

Inorganic Chemistry, Nov 3, 2011

Two uranyl nanotubules with elliptical cross sections were synthesized in high yield from complex... more Two uranyl nanotubules with elliptical cross sections were synthesized in high yield from complex and large oxoanions using hydrothermal reactions of uranyl salts with 1,4-benzenebisphosphonic acid or 4,4′-biphenylenbisphosphonic acid and Cs + or Rb + cations in the presence of hydrofluoric acid. Disordered Cs + /Rb + cations and solvent molecules are present within and/or between the nanotubules. Ion-exchange experiments with A 2 {(UO 2 ) 2 F(PO 3 HC 6 H 4 C 6 H 4 PO 3 H)(PO 3 HC 6 H 4 C 6 H 4 PO 3 )}•2H 2 O (A = Cs + , Rb + ), revealed that A + cations can be exchanged for Ag + ions. The uranyl phenyldiphosphonate nanotubules, Cs 3.62 H 0.38 [(UO 2 ) 4 {C 6 H 4 (PO 2 OH) 2 } 3 {C 6 H 4 (PO 3 ) 2 }F 2 ]•nH 2 O, show high stability and exceptional ion-exchange properties toward monovalent cations, as demonstrated by ion-exchange studies with selected cations, Na + , K + , Tl + , and Ag + . Studies on ionexchanged single crystal using scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDS) provide evidence for chemical zonation in Cs 3.62 H 0.38 [(UO 2 ) 4 {C 6 H 4 (PO 2 OH) 2 } 3 {C 6 H 4 (PO 3 ) 2 }F 2 ]•nH 2 O, as might be expected for exchange through a diffusion mechanism. ■ EXPERIMENTAL SECTION Synthesis. UO 2 (NO 3 ) 2 •6H 2 O (98%, International Bio-Analytical Industries), HF (48 wt %, Aldrich), 4,4′-biphenylenebisphosphonic acid (98%, Epsilon Chimie), 1,4-benzenebisphosphonic acid (95%, Epsilon Chimie), sodium chloride, potassium chloride, rubidium chloride, cesium chloride, thallium nitrate, silver nitrate, and strontium chloride hexahydrate (Alfa Aesar) were used as received. Reactions were run in PTFE-lined Parr 4749 autoclaves with a 23 mL internal

Download

CCDC 912909: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Syntheses, Structure Elucidation, and Properties of Novel Actinide Diphosphonates and Carboxyphosphonates

Hybrid Uranium–Transition-Metal Oxide Cage Clusters

Inorganic Chemistry, Dec 1, 2014

Transition-metal based polyoxometalate clusters have been known for decades, whereas those built ... more Transition-metal based polyoxometalate clusters have been known for decades, whereas those built from uranyl peroxide polyhedra have more recently emerged as a family of complex clusters. Here we report the synthesis and structures of six nanoscale uranyl peroxide cage clusters that contain either tungstate or molybdate polyhedra as part of the cage, as well as phosphate tetrahedra. These transition-metaluranium hybrid clusters exhibit unique polyhedral connectivities and topologies that include 6-, 7-, 8-, 10-, and 12-membered rings of uranyl polyhedra and uranyl ions coordinated by bidentate peroxide in both trans and cis configurations. The transitionmetal polyhedra appear to stabilize unusual units built of uranyl polyhedra, rather than templating their formation.

Download

Comparison of Thorium(IV) and Uranium(VI) Carboxyphosphonates

Inorganic Chemistry, May 13, 2010

Download

Differential Ion Exchange in Elliptical Uranyl Diphosphonate Nanotubules

Angewandte Chemie, Oct 12, 2010

Uranyl materials with nanotubular structures represent a very small subset of the thousands of ur... more Uranyl materials with nanotubular structures represent a very small subset of the thousands of uranyl compounds that have been prepared with only handful of examples being known thus far. The first of these that was discovered is a uranyl phenylphosphonate (γ-UPP) where the phenyl groups create the hydrophobic exterior of the nanotubules. Three other examples are uranyl selenates prepared via the slow evaporation of uranyl selenate solutions in the presence of organic templates or alkali metal cations. In addition an uranyl formate adopts nanotubulular structure. Very little is known about whether compounds in this class only represent interesting structures, or whether atypical properties can be derived from their unusual architectures. This presentation will highlight results from our studies with aryl diphosphonates and the first demonstration of ion-exchange in uranyl diphosphonate nanotubules.

Download

Pillared and open-framework uranyl diphosphonates

Journal of Solid State Chemistry, Sep 1, 2011

The hydrothermal reactions of uranium trioxide, uranyl acetate, or uranyl nitrate with 1,4-benzen... more The hydrothermal reactions of uranium trioxide, uranyl acetate, or uranyl nitrate with 1,4-benzenebisphosphonic acid in the presence of very small amount of HF at 200°C results in the formation of three different uranyl diphosphonate compounds, [H3O]2{(UO2)6[C6H4(PO3)(PO2OH)]2[C6H4(PO2OH)2]2[C6H4(PO3)2]}(H2O)2 (Ubbp-1), [H3O]4{(UO2)4[C6H4(PO3)2]2F4}·H2O (Ubbp-2), and {(UO2)[C6H2F2(PO2OH)2(H2O)}2·H2O (Ubbp-3). The crystal structures of these compounds were determined by single crystal X-ray diffraction experiments. Ubbp-1 consists of UO7

Incorporation of Cu2+ Ions into Nanotubular Uranyl Diphosphonates

Inorganic Chemistry, Apr 4, 2014

Three new multidimensional polymetallic uranyl diphosphonates were crystallized under mild hydrot... more Three new multidimensional polymetallic uranyl diphosphonates were crystallized under mild hydrothermal conditions: [Cu(H2O)]2{(UO2)4F2[(PO3C6H4)(C6H4PO3H)3]2(bipym)}·6H2O (1), [Cu(H2O)]2{(UO2)4[(C6H4PO3)(C6H4PO3H)]4(bipym)} (2), and Cu{(UO2)(C6H4PO3)2(bipym)}·H2O (3). Compound 1 consists of UO6F pentagonal bipyramids connected by diphosphonate moieties into a tubular channel. The Cu(2+) cations are stabilized between the nanotubular subunits by 2,2&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-bipyrimidine (bipym). The structure of 2 is similar to 1, except that it consists of relatively rare UO6 tetragonal bipyramids bridged by diphosphonate groups. Compound 3 also contains UO6 tetragonal bipyramids. Unlike compounds 1 and 2, only two of the tetradentate N atoms of the binucleating bipym group are coordinated. All three compounds show luminescent properties under ambient conditions, with evidence of the characteristic vibronically coupled charge-transfer based uranyl cation emissions.

Role of magnetic concentration in modulating the magnetic properties of ultra-small FePt nanoparticles

Inorganica Chimica Acta, Apr 1, 2017

Magnetic characterization of nanoscale materials is often hindered by the role that sample prepar... more Magnetic characterization of nanoscale materials is often hindered by the role that sample preparation techniques play in the determination of interparticle interaction strength. Well-dispersed d = 2.6(4) nm FePt nanoparticles synthesized by a slight modification of a known polyol synthesis were employed to study this effect at the extreme lower limit of the nanoscale regime. Suspension in a diamagnetic matrix material at varying concentrations was used to characterize the relationships between average particle distance and representative magnetic properties (zero-field cooled/field-cooled (ZFC/FC) magnetization curves, hysteresis M(H) loops at 5 K, and ac-susceptibility). By increasing the interparticle distance through diamagnetic dilution, the blocking temperature (T B ), anisotropy energy barrier (U eff ), and coercive field (H c ) drop continuously until reaching a dilution ratio where the magnetic signals were limited by the competing diamagnetic contribution from the matrix material. Long-timescale blocking temperature and coercivity are relatively unaffected by particle dilution while the shorter timescale anisotropy energy barrier (U eff ) and attempt time (s 0 ) are strongly affected. These results demonstrate the need for well-defined sample preparation conditions when comparing materials properties, especially those with applications dependent on superparamagnetism.

Download

Uranyl-Organic Hybrids Designed from Hydroxyphosphonate

European Journal of Inorganic Chemistry, Dec 9, 2014

A series of phosphonate‐based uranyl–organic hybrids has been assembled based on the reaction of ... more A series of phosphonate‐based uranyl–organic hybrids has been assembled based on the reaction of uranyl cations with 2,5‐dihydroxy‐1,4‐benzenediphosphonic acid in the presence of a variety of alkali metal and organoammonium cations: K[(UO2)2F2{H0.5O3PC6H2(OH)2PO3H0.5}](H2O)2 (1), Cs[(UO2)2{H0.75O3PC6H2(OH)2PO3H0.75}](H2O)4·2H2O (2), [(CH3)4N]2[UO2{HO3PC6H2(OH)2PO3H}2] (3), [(CH3CH2)4N][UO2F{HO3PC6H2(OH)2PO3H}] (4), and [(CH3CH2)2N(CH3)2][UO2F{HO3PC6H2(OH)2PO3H}] (5). In compounds 1, 4, and 5, chains of UO5F2 pentagonal bipyramids are linked by the hydroxyphosphonate moiety into three‐dimensional frameworks, and compound 4 is isostructural with 5. However, the structures of 2 and 3 are composed of monomeric UO7 pentagonal bipyramids assembled to form layered structural units. Additional steric influences from the –OH groups appended on the diphosphonate species play a vital role in directing the structure topologies.

Use of 2,2-Bipyrimidine for the Preparation of UO22+-3d Diphosphonates

Crystal Growth & Design, Oct 22, 2014

Three new multidimensional bimetallic UO22+-3d three-dimensional complexes were crystallized in h... more Three new multidimensional bimetallic UO22+-3d three-dimensional complexes were crystallized in high yield under mild hydrothermal conditions: [Mn(H2O)]2[(UO2)4(PO3C6H4PO3)3(bipym)]·2H2O (1), [Ni(H2O)]2[(UO2)3(O3PC6H4PO3)(O3PC6H4PO3H)2(bipym)]·6H2O (2), and Zn[(UO2)(HO3PC6H4PO3)(HO3PC6H4PO3H)0.5(bipym)0.5] (3), where bipym = 2,2-bipyrimidine. The structure of 1 is composed of edge-sharing dimers of uranyl pentagonal bipyramids that are linked by rigid phenyl spacers to form pillared three-dimensional networks. This compound is remarkable in that the [Mn2(H2O)2(bipym)]4+ moiety is incorporated within the uranyl phosphonate frameworks without reducing the dimensionality of the overall structure. Compound 2 consists of uranyl tetragonal and pentagonal bipyramids that are linked by phosphonate groups to form a pillared three-dimensional framework with channels that are occupied by the [Ni2(H2O)2(bipym)2]4+ moiety. In compound 3, edge-sharing dimers of uranyl pentagonal bipyramids are connected through the pho...

Hybrid Uranyl-Carboxyphosphonate Cage Clusters

Inorganic Chemistry, Jun 13, 2013

Download

Correlations and Differences between Uranium(VI) Arsonates and Phosphonates

Inorganic Chemistry, Oct 25, 2012

Download

Thorium and uranium diphosphonates: Syntheses, structures, and spectroscopic properties

Journal of Solid State Chemistry, Aug 1, 2012

Four new thorium and uranium diphosphonate compounds, [H 3 ) have been synthesized hydrothermally... more Four new thorium and uranium diphosphonate compounds, [H 3 ) have been synthesized hydrothermally using 1,4-benzenebisphosphonic acid as ligand. The crystal structures of these compounds were determined by single crystal X-ray diffraction. Thbbp-1 and Thbbp-2 contain seven-coordinate Th(IV) within ThO 6 F and ThO 7 units with capped trigonal prismatic and capped octahedral geometries, respectively. U4bbp is isotypic with Thbbp-2. The structure of U6bbp contains U(VI) is the common seven-coordinate pentagonal bipyramid.

Download

High Nuclearity Uranyl Cages Using Rigid Aryl Phosphonate Ligands

European Journal of Inorganic Chemistry, Dec 5, 2019

Two high nuclearity uranyl cages were crystallized in high yield under mild solvothermal conditio... more Two high nuclearity uranyl cages were crystallized in high yield under mild solvothermal conditions using rigid aryl phosphonate ligands. These compounds are prepared either through an in situ phosphonate ligand condensation reaction or via serendipitous assembly with a bulky phosphonate ligand. Firstly, the flexibility of the phosphonate ligands enhances the curvature of the uranyl polyhedra in the assembly of both compounds. Secondly, the formation of bent pyrophosphonate li- [a]

Download

ChemInform Abstract: Hybrid Uranium-Transition-Metal Oxide Cage Clusters

ChemInform, Feb 19, 2015

Hybrid Uranium-Transition-Metal Oxide Cage Clusters. -The cage clusters (IV) and (VI)-(X) are sel... more Hybrid Uranium-Transition-Metal Oxide Cage Clusters. -The cage clusters (IV) and (VI)-(X) are self-assembled in aqueous solution under ambient conditions and subsequently crystallized. They contain either tungstate or molybdate polyhedra as part of the cage, as well as phosphate tetrahedra. The clusters exhibit unique polyhedral connectivities and topologies that include 6-, 7-, 8-, 10-, and 12-membered rings of uranyl polyhedra and uranyl ions coordinated by bidentate peroxide in both trans and cis configuration. Compound (IX) crystallizes in the space group P6 3/mmc with Z = 2. (IV), (VII), and (VIII) crystallize in the space group P1 with Z = 2. (VI) crystallizes in the space group Pmn2 1 with Z = 2, and (X) in the space group P4/n with Z = 2. -

Download

CCDC 813711: Experimental Crystal Structure Determination

Hydrothermal Synthesis and Structural Characterization of Organically Templated Uranyl Diphosphonate Compounds

Crystal Growth & Design, Mar 30, 2011

ABSTRACT

Pius Adelani

Uploads

Papers by Pius Adelani

Log In