Key indicatorsSingle-crystal X-ray study T = 293 K Mean (C-C) = 0.003 Å R factor = 0.050 wR factor = 0.156 Data-to-parameter ratio = 16.5For details of how these key indicators were automatically derived from the article, see

No abstract

In the title structure, C21H16Cl2N2, the pyrazoline ring makes dihedral angles of 6.76 (9), 7.52 (10) and 81.88 (10)°, respectively, with the 4‐chloro­phenyl ring, the phenyl ring and the 2‐chlorophenyl ring. The 5‐phenyl ring is almost perpendicular to the pyrazoline ring.

In the title molecule, C18H17N3O3, all bond lengths and angles show normal values. The two benzene rings make a dihedral angle of 87.27 (2)°. Weak intermolecular C—H...O hydrogen bonds stabilize the crystal packing.

1-Acetyl-3-(4-chlorophenyl)-5-(4-methylphenyl)-2-pyrazoline has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. Density functional (DFT) calculations have been carried out for the title compound by using the B3LYP method at the 6-311G** basis set level. The calculated results show that the predicted geometry can reproduce well the structural parameters. Predicted vibrational frequencies have been assigned and compared with experimental IR spectra and they are supported each other. On the basis of vibrational analyses, the thermodynamic properties of the title compound at different temperatures have been calculated, revealing the correlations between C0p, m, S0m, H0m and temperatures.