| dc.description |
The potential of photoacoustic spectroscopy to resolve the crystal field levels of Cu<sup>2+</sup> ions in three polyamine copper complexes, aqua spermine copper sulfate trihydrate [NH<sub>2</sub>(CH<sub>2</sub>)<sub>3</sub>NH(CH<sub>2</sub>)<sub>4</sub>NH(CH<sub>2</sub>)<sub>3</sub>NH<sub>2</sub>·Cu<sup>2+</sup>·H<sub>2</sub>O]·SO<sub>4</sub><sup>2-</sup>·3H<sub>2</sub>O, norspermine copper sulfate trihydrate [NH<sub>2</sub>(CH<sub>2</sub>)<sub>3</sub>NH(CH<sub>2</sub>)<sub>3</sub>NH(CH<sub>2</sub>)<sub>3</sub>NH<sub>2</sub>·Cu<sup>2+</sup>·SO<sub>4</sub><sup>2-</sup>]·3H<sub>2</sub>O, and homospermine copper sulfate dihydrate [NH<sub>2</sub>(CH<sub>2</sub>)<sub>3</sub>NH(CH<sub>2</sub>)<sub>2</sub>NH(CH<sub>2</sub>)<sub>3</sub>NH<sub>2</sub>·Cu<sup>2+</sup>·SO<sub>4</sub><sup>2-</sup>] ·2H<sub>2</sub>O, has been explored along with UV/VIS and electron paramagnetic resonance (EPR) spectroscopy. Intense absorption is detected in the photoacoustic spectrum corresponding to the d-d transition band weakly traced in the corresponding optical spectrum. The observed fine structure photoacoustic lines are assigned to the individual d-d transitions of Cu<sup>2+</sup> ions, which are further exploited to determine the diverse metal-ligand interaction of the studied compound employing simple crystal field analysis. |
