The stereochemistry of the actinide elements has recently undergone considerable development and a wide variety of coordination numbers and geometries have been observed. This structural versatility arises from the lack of strong crystal field effects for the 5f-electronic configurations as well as from the large ionic radii of these metal ions, which change markedly with oxidation number, ...

The hydrolysis of the thorium(IV) ion in various concentrations of magnesium, calcium, strontium and barium chloride media was studied by the emf method at 25 °c. The data show that the extent of thorium hydrolysis decreases with increasing concentration and hydration energy of the medium ions. The contribution of the concentration of the medium ions to the total medium effect is higher than th...

Since the 1960s, thorium isotopes occupy a special place in the oceanographer’s toolbox as tracers for determining rates and mechanisms of oceanic scavenging, particle dynamics, and carbon fluxes. Due to their unique and constant production rates from soluble parent nuclides of uranium and radium, their disequilibrium can be used to calculate rates and time scales of sinking particles. In addit...

The sorption of thorium and uranium ions by functionalized SBA–15 mesoporous silica materials with Schiff base ligating groups N–propylsalicylaldimine (SBA/SA) and ethylenediaminepropylesalicylaldimine (SBA/EnSA) from aqueous solution was investigated in fixed-bed column method. The TEMPeffect of pH, sample solution volume, and the column design parameters such as sample and eluent flow rat...

Phosphinoylated calixarenes feature high coordination ability toward f elements and a great potentiality toward actinide/rare earth separation. Here, we report three characteristic properties of a tetra-phosphinoylated p-tert-butylcalix[4]arene, B4bL functionalized with phosphinoyl pendant arms: (i) its coordination ability toward Th(IV) complexation in organic medium, (ii) its ability to separ...

The reactivity of the monoanionic amidinate ligand [(CH3)3CNC(Ph)NSiMe2NC(Ph)-NHC(CH3)3]Li (1) with a silyl amido side arm towards the early actinides, uranium and thorium, was investigated. While the salt metathesis reaction with ThCl4(thf)3 afforded the bis(amidinate)thorium(iv) dichloride complex [(CH3)3CNC(Ph)NSi(CH3)2NC(Ph)-NHC(CH3)3]ThCl2 (2) in high yield, the reaction of ligand 1 with U...

N-[(Diphenylamino)methyl]acetamide was synthesized using Mannich reaction and its complexes of cerium(IV), thorium(IV) and dioxouranium(VI) were prepared and characterized by elemental analysis and various spectral studies. The bidendate chelation of ligand, bonding through carbonyl oxygen and azomethine nitrogen is suggested. Based on spectral and magnetic studies, hexa coordinate geometry is ...

The present work describes the studies on the coordination behaviour of 4[N-(benzalidene) amino]antipyrine semicarbazone (BAAPS) (I), 4[N-(furfural)amino]antipyrine semicarbazone (FFAAPS) (II) and 4[N-(cinnamalidene)amino]antipyrine semicarbazone (CAAPS) (III) in presence of dimethyl sulfoxide (DMSO) or diphenyl sulfoxide (DPSO) towards Th4+ and UO22+ salts. All the complexes were isolate...