title: Ab initio HF, DFT and experimental (FT-IR) investigation of vibrational spectroscopy of 3-(2-(4-isopropylpiperazin-1-yl)-2-oxoethyl)-6-(4-methoxybenzoyl)benzo[d]thiazol-2(3H)-one.
abstract: FT-IR spectra was recorded for 3-(2-(4-isopropylpiperazin-1-yl)-2-oxoethyl)-6-(4-methoxybenzoyl)benzo[d]thiazol-2(3H)-one molecule (abbreviated as IOMBT) sample in solid state. Conformational analysis of IOMBT was performed to determine the most stable conformer. Potential energy curves of IOMBT were obtained performing a relaxed scan of D1-7 dihedral angels at B3LYP/6-311++G(d,p) level of theory. Geometrical parameters of these structures were optimized by using the same method. The molecular geometry of IOMBT was reoptimized at DFT(B3LYP) and HF methods using 6-311++G(d,p), 6-311+G(d), 6-311G(d,p), 6-311G(d) and 6-31++G(d,p) basis sets for the lowest energy conformer. The vibrational frequencies, IR intensities were calculated at DFT(B3LYP) and HF methods. The thermodynamic parameters (such as zero-point vibrational energy, EHOMO, ELUMO, thermal corrections to energy, enthalpy and Gibbs free energy, and entropy) have also been computed. The LUMO-HOMO energy gap of IOMBT shows that the energy gap reflects the chemical reactivity and the level of conductivity of the molecule.
authors.affiliation: Department of Physics, Faculty of Arts & Sciences, Eskişehir Osmangazi University, 26480 Eskişehir, Turkey. eroltasal@gmail.com
authors.forename: Erol
authors.initials: E
authors.lastname: Taşal
authors.forename: Mustafa
authors.initials: M
authors.lastname: Kumalar
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010879:Piperazines / Q000737:chemistry*; D011789:Quantum Theory; D017550:Spectroscopy, Fourier Transform Infrared; D013816:Thermodynamics; D013844:Thiazoles / Q000737:chemistry*
chemical_list: C581183:3-(2-(4-isopropylpiperazin-1-yl)-2-oxoethyl)-6-(4-methoxybenzoyl)benzo(d)thiazol-2(3H)-one; D000894:Anti-Inflammatory Agents, Non-Steroidal; D010879:Piperazines; D013844:Thiazoles