Synthesis, crystal growth, characterization and Hirshfeld surface analysis of D-π-A-π-D type NLO chalcone

A chalcone with molecular formula C13H10OS2 has been synthesized by Claisen-Schmidt condensation reaction method. Single crystals were grown by slow evaporation solution growth method. Single crystal X-ray diffraction data shows that the compound crystallized in orthorhombic system with centrosymmetric space group Pbca. From the thermo gravimetric/differential thermal analysis the melting point of the compound was found to be 118°C and the material is chemically stable up to 210°C. The UV-visible spectrum shows a peak at wavelength 357nm and has been assigned to n→π* transition is due to intra molecular charge transfer. The molecule has better transparency in the blue-green region (λcut off = 437nm). The Vicker’s micro hardness test was employed to measure the mechanical stability of the crystal and the hardening coefficient (n) of the crystal was found to be 1.66. The static molecular first and second hyperpolarizability were computed using MOPAC 2016. The static second hyperpolarisability calculated for the molecule was compared with the chalcone molecules reported in the literature which revealed the better NLO performance of the present chalcone. The HOMO - LUMO plot clearly reveals that the DTPD molecule belongs to D-π- A-π-D type charge transfer structure. To explore the intermolecular interactions in the crystal the Hirshfeld surface analysis and related 2D finger print plots were generated using crystal Explorer 17.5. It is evident from the Hirshfeld surface analysis that the major contribution to the crystal structure stability is due to H…H (37.4%), C…H (28.4%), S…H(13%) and H…O (8.7%) interactions.