Search Results

You are looking at 1 - 10 of 48 items for :

  • "coordination chemistry" x
Clear All
Journal of Thermal Analysis and Calorimetry
Authors: W. Ludwig, M. Döring, R. Fischer, A. Friedrich, W. Seidel, E. Uhlig and D. Walther
Restricted access

Abstract  

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.

Restricted access

Contributions to the coordination chemistry of technetium

I. Complexes of technetium-(I) with amino acids

Journal of Radioanalytical and Nuclear Chemistry
Authors: F. Schöster and S. Zeisler

Abstract  

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.

Restricted access

Contribution to the coordination chemistry of technetium

II. Complexes of technetium (I) with selected ligands containing N, O and S doner atoms

Journal of Radioanalytical and Nuclear Chemistry
Authors: F. Schöster and S. Zeister

Abstract  

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.

Restricted access

Abstract  

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.

Restricted access

Mechanical mixing of molecular crystals

A green route to co-crystals and coordination networks

Journal of Thermal Analysis and Calorimetry
Authors: D. Braga, S. Giaffreda, M. Curzi, Lucia Maini, M. Polito and Fabrizia Grepioni

Abstract  

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.

Restricted access

Abstract  

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.

Restricted access

Abstract  

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 4 . 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.

Restricted access

. 15 49 127 Poonia, N. S. (1974): Coordination chemistry of sodium and potassium complexation with macrocyclic polyethers. J. Am. chem. Soc , 96

Restricted access