RESUMEN
A new solvatochromic complex of copper (II) and 3H-indolium (HQIndol) with the formula (HQIndol)3Cu has been synthesised and characterised by elemental analysis, UV-vis, IR spectroscopies, electron paramagnetic resonance (EPR), and static magnetic susceptibility and conductance measurements. The stoichiometry of complex has been determined as 1:3 (M:L) and the binding constant was calculated to be 5.86×10(16) mol(-1) L at 25 °C in CH3OH. Magnetization measurements indicate that (HQIndol)3Cu sample is paramagnetic with spin S=1/2 for which phase transition from paramagnetic to antiferromagnetic has been registered at TN=2.5 K. The symmetry of the EPR spectrum points to elongated tetragonal octahedral geometry of the complex. Examined heterochelate exhibits solvatochromic properties. Blue shift of the vis absorption band with increased solvent polarity is observed, Δνâ¾max in examined solvents amounts to 1466 cm(-1).
Asunto(s)
Cobre/química , Indoles/química , Fenómenos Magnéticos , Solventes/química , Tritio/química , Anisotropía , Conductividad Eléctrica , Espectroscopía de Resonancia por Spin del Electrón , Ligandos , Espectroscopía de Protones por Resonancia Magnética , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , TemperaturaRESUMEN
A new electrochemical method for the determination of trace water in methanol has been developed. This method is based on the effect, that a minor change in the water content affects the value of conductivity measured for dissolved in the solutions electrolyte. The conductivity measurements were performed for four inorganic salts, i.e. NaCl, KCl, RbCl, and CsCl in solutions with different amounts of water traces in methanol and the calibration curves for three of them were determined. With the exception of cesium chloride the high values of correlation coefficients for the regression lines as well as low limits of detection were achieved in all cases which indicates that this method is a useful tool for the determination of the trace amounts of water in methanol.