This study reports chromotropism of two newly synthesized copper(II) complexes of formula [CuLCl2] and [CuLBr2]•MeOH where L = N-(2-pyridylmethyl)-1-hydroxypropylamine. The structure of the complexes was investigated by infrared spectroscopy, electronic absorption spectroscopy, elemental analysis, molar conductance measurements, and thermal analysis. Single Crystal X-ray structure determination reveals both complexes to adopt a distorted square-pyramidal geometry. Their chromotropic properties were investigated using electronic absorption spectroscopy. The complexes are solvatochromic in solvents with different polarities. The aqueous solutions of the complexes exhibit a variety of colors in the pH range of 1.8 to 11.4 showing that the compounds are halochromic. The complexes are also thermochromic and show reversible color changes in different temperatures in dimethyl sulfoxide solutions. The solution study reveals that the observed chromotropism originates from structural changes of the complexes in different conditions.
