Authors:Yu. Barbanel', V. Kolin, V. Kotlin and A. Lumpov
The problems of actinide molten salt coordination chemistry are considered in terms of spectroscopic parameters as functions of melt composition and temperature. Parameters connected with energy, intensity and fine structure of 5f-5f transitions have been obtained for molten alkali metal chlorides, fluorides and chloride-fluoride mixtures. The regularities of variation of both actinide-chlorine distances and actinide fluorocomplex stability have been studied.
The radionuclide99mTc is widely used in nuclear medical diagnostics. Radiopharmaceuticals containing coordination compounds labeled with99mTc4+ or99mTc5+ can be rapidly prepared from pertechnetate eluted from a99Mo/99mTc generator. For the optimization of the imaging agent it is essential to determine the exact chemical structure of the Tc complex. This can be achieved by synthesizing macroscopic amounts of the analogous long-lived99gTc compound and by its analysis by appropriate spectroscopy methods. We have successfully synthesized and characterized new technetium complexes with amino acids and also with ligands containing nitrogen, oxygen and sulfur atoms.
The universal use of radiophamaceuticals labeled with99mTc has led to the development of many Tc complexes containing99mTc4+ or99Tc5+. In order to assess the correlation between the physiological properties and the chemcial structure of a99mTc complex, milligramm amounts of the corresponding long-lived99gTc compound have to be synthesized and analyses. This report describes the synthesis and characterization of several new technetium complexes with ligands containing N, O and S as donor atoms.
Physicalo-chemical importance of the quantitative study of kineticliability of coordination compounds in thermal dissociation
processes is considered. Muchattention is given to the proof of the physicalo-chemical meaning and validity of kineticparameters
calculated from thermoanalytical data. Experimental data (thermal dissociation ofcoordination compounds and clathrates with
such a matrix) are discussed.
Authors:D. Braga, S. Giaffreda, M. Curzi, Lucia Maini, M. Polito and Fabrizia Grepioni
Supramolecular reactions between crystalline materials can be exploited to prepare both hydrogen bonded co-crystals and coordination
networks. Mechanical mixing of molecular crystals as well as kneading provide an alternative, solvent-free, route to novel
materials hence these methods represent a green route to supramolecular solid-state chemistry.
Authors:Dean Peterman, Leigh Martin, John Klaehn, Mason Harrup, Mitchell Greenhalgh and Thomas Luther
A new extractant for the separation of actinide(III) and lanthanide(III) cations, bis(o-trifluoromethylphenyl) phosphinic acid (2) was synthesized. The synthetic route employed mirrors one that was employed to produce the sulfur containing analog bis(o-trifluoromethylphenyl) dithiophosphinic acid (1). Classic radiochemical methods and absorbance spectroscopy were used to study the coordination chemistry of the Am-dithiophosphinic
acid and Am-phosphinic acid complexes.
Solid complexes of five derivatives of thio-Schiff bases with La(III) and Ce(III) ions were prepared and characterized by
elemental and thermogravimetric analyses. The suggested general formula of the solid complexes is [ML2(H2O)X]·2H2O, whereM=trivalent lanthanide ion,L=Schiff base andX=Cl− or ClO
. Information about the water of hydration, the coordinated water molecules, the coordination chemistry and the thermal stability
of these complexes was obtained and is discussed. Additionally, a general scheme of thermal decomposition of the lanthanide-Schiff
base complexes is proposed.