Crown Ethers Thorium(Ⅳ) Nitrate Hydrate 착물에 관한 연구 = Hydrated Thorium(Ⅳ) Nitrate Complexes with Crown Ethers Ligands(Ⅰ)

다국어 초록 (Multilingual Abstract)

The hydrated thorium(Ⅳ) nitrate have been reacted with the crown ethers of the different cavity size in methanol and aceton solvent, respectively.
The properties and structures of these complexes are discussed by the element analysis, Kahl-Fisher moisture titration, thermal analysis, X-ay diffraction, ultraviolet and infrared spectroscopy, and electric conductivity.
All of the complexes and the nonaccordinated systems with the three, four and five molecules of the hydrates, and the mole ratio of metallic ion to crown ether ligands are 1:1. The structures of the all complexes are different in accordance with the kinds of solvents, but coordinating number and mole ratio are constant in all complexes.
The molar absorptivity of the complex obtained in aceton solvent is increased by coordinated bonding of the thorium(Ⅳ) ion to the ligands because the coordinating power of molecule of aceton is larger than that of water.
The hydrated thorium(Ⅳ) nitrate complexes with crown ethers have the structure of 1:4 electrolytes deduced from 466-479 ohm^-lcm M^-1.
These complexes have been formed by the electrostatic attraction and it is found the hydrated thorium(Ⅳ) nitrate complex with 15-crown-5 ligand is the most stable because thorium(Ⅳ) ion is bonded inside of the ligands. Whereas the other complexes are bonded outside of the cavity of the crown ether because the size of thorium(Ⅳ) ion is smaller or larger than that of the other crown ethers.