Synthesis and structural analysis of a new polymorph of [Cu^II(PMDETA)Br₂]

ABSTRACT

A new polymorph of [Cu^II(PMDETA)Br₂] has been recognized and characterized by X-ray structural studies at two different temperatures (120 and 298°K). The results indicated the existence of a monoclinic crystalline system for [Cu^II(PMDETA)Br₂] grown in CH₃OH or CH₃CN with a distorted square pyramid geometry. The supramolecular structure of this complex has been studied using geometrical and Hirshfeld surface analysis. From lattice energy calculation, it has been shown that the newly found polymorph is thermodynamically more stable than the previously recognized one. UV-vis spectroscopy confirmed complex formation between Cu^IIBr₂ and PMDETA in CH₃OH and CH₃CN, which was accompanied by peak displacement. FTIR spectroscopy, differential scanning calorimetry, and scanning electron microscopy were also used to get insights about the formation of this new polymorph of [Cu^II(PMDETA)Br₂].

KEYWORDS:

• Inorganic polymorphs
• PMDETA
• Copper(II) coordination complexes