Crystal structure and optical spectroscopic analyses of (E)-3-(1H-indol-2-yl)-1-(4-nitro-phen-yl)prop-2-en-1-one hemihydrate.

The asymmetric unit of the title compound, 2C(17)H(12)N(2)O(3)·H(2)O comprises two mol-ecules of (E)-3-(1H-indol-2-yl)-1-(4-nitro-phen-yl)prop-2-en-1-one and a water mol-ecule. The main mol-ecule adopts an s-cis configuration with respect to the C=O and C=C bonds. The dihedral angle between the indole ring system and the nitro-substituted benzene ring is 37.64†(16)°. In the crystal, mol-ecules are linked by O--H⋯O and N-H⋯O hydrogen bonds, forming chains along [010]. In addition, weak C-H⋯O, C-H⋯π and π-π inter-actions further link the structure into a three-dimensional network. The optimized structure was generated theoretically via a density functional theory (DFT) approach at the B3LYP/6-311†G++(d,p) basis level and the HOMO-LUMO behaviour was elucidated to determine the energy gap. The obtained values of 2.70†eV (experimental) and 2.80†eV (DFT) are desirable for optoelectronic applications. The inter-molecular inter-actions were qu-anti-fied and analysed using Hirshfeld surface analysis.