Enhanced SHG performance of Cd 2+ doped DAST crystal featuring charge exchange owing metal ion-organic ligand for NLO applications

Abstract

The slow evaporation solution (SEST) technique was used to grow a CdSO4 (5 %) doped DAST (CdS5-DAST) single crystal. The structural properties of the grown CdS5-DAST single crystal were investigated using single crystal X-ray Diffraction (SXRD) analysis. The SXRD data reveals that the CdS5-DAST crystal is non-centrosymmetric with a monoclinic (Cc) space group. The existence of a metal–organic 5 % of CdSO4 in DAST was affirmed by energy dispersive spectroscopy analysis (EDAX). The optical property of the grown single crystal was investigated by a UV–vis-NIR spectrometer, which showed the absorption cut-off wavelength is 380 nm. As a result, the electronic transition from non-bonding molecular orbital (ground) states to antibonding molecular orbital (excited) states corresponds to the absorption λ maximum. The energy (ΔE) requirement is small enough for electrons to transition from n-π* states. The optical bandgap (Eg), refractive index and extinction coefficient of the CdS5-DAST single crystal are calculated. As a result, crystals have an optical bandgap of 2.1 eV. Cd2+ doped DAST crystal enhances SHG performance significantly, owing to charge exchange facilitated by the metal ion-organic ligand and electron density. The grown CdS5-DAST crystal has a best SHG response and compared to the some organic NLO crystals. The PL spectrofluorometer study substantiates that green emission features at a wavelength of 527 nm. TG-DTA was being used to analyze the thermal characteristics of the crystal was thermally stable up to 259.95 °C.