Quantum chemical studies and effect of gamma irradiation on the spectral, thermal, X‐ray diffraction and DNA interaction with Pd (II), Cu(I), and Cd (II) of hydrazone derivatives

Abstract

A new series of Pd (II), Cd (II), and Cu(I) complexes with ((Z)‐2‐(phenylamino)‐N′‐(thiophen‐2‐ylmethylene)acetohydrazide)( H 2 L B ) has been prepared. FT‐IR, 1 H‐NMR, electronic spectra, Powder X‐ray, thermal behavior, theoretical methods and DNA interaction of ligand and of Pd (II) and Cu(I) complexes before and after γ‐irradiation are studied. The 1 H NMR spectrum of the ligand after γ‐irradiation shows the signals appear at the same position or slightly shift, but the intensity of the bands after γ‐irradiation is higher than before irradiated. X‐ray diffraction (XRD) studies exhibited the samples in nanorange, the crystallite size is 1.94, 4.81 nm for both unirradiated (B 1 and B 3 ) and 2.93, 4.72 nm for irradiated (A 1 and A 3 ). The thermal stability of the complexes after γ‐irradiation increase than before γ‐irradiation. The possible structures of the metal complexes have been computed using the molecular mechanic calculations UFF using quantum chemical software by Gaussian 09 W program. The calculations are performed with DFT/B3LYP/LANL2DZ to obtain the optimized molecular geometry. Some important quantum chemical descriptors of the metal complexes were calculated such as HOMO, LUMO, and energy gap. Metal complexes before and after irradiation in the absence and presence of increasing amounts of CT‐DNA exhibit that the absorption intensities decrease with increasing the concentration of DNA.