2015. 56, 5 UDC 548.737 MOLECULAR STRUCTURE AND VIBRATIONAL AND CHEMICAL SHIFT ASSIGNMENTS OF (4R)-5-ENO-4,7-EPIDIOXY-3,7-O-METHYL-1,2-O-(S)TRICHLOROETHYLIDENE-5,6,8-TRIDEOXY-h-D-THREO-1,4-FURANO4,7-DIULO-OCTOSE BY DFT AND AB INITIO HF CALCULATIONS T. Karakurt1, M. Dinзer2, F. Зetin3 1Department of Chemical Engineering, Faculty of Engineering and Architecture, Ahi Evran University, Krehir, Turkey E-mail: tuncaykarakurt@gmail.com 2Department of Physics, Faculty of Sciences, Ondokuz Mays University, Samsun, Turkey 3Department of Chemistry, Faculty of Arts and Sciences, Ege University, zmir, Turkey Received February, 12, 2014 Revised — July, 31, 2014 Elemental analyses, single crystal X-ray diffraction method, and 1H and 13C NMR spectral techniques are used to synthesize and characterize the crystal structure of 4-diethylamino-2{[4-(3-methyl-3-phenyl-cyclobutyl)-thiazol-2-yl]-hydrazonomethyl}-phenol. <...> In order to calculate the molecular geometry along with vibrational frequencies and the gauge including atomic orbital (GIAO) 1H and 13C NMR chemical shift values of the title crystal structure in the ground state, the Hartree—Fock (HF) and density functional theory (DFT) methods with 6311G(d,p) basis sets are utilized. <...> The assignments of the vibrational frequencies are calculated with the help of the potential energy distribution (PED) analysis using the VEDA 4 software. <...> The molecule contains C—H O intra—inter— molecular interactions. <...> DOI: 10.15372/JSC20150510 Keywords: X-ray structure determination, DFT, HF, GIAO, 1H and 13C NMR, IR spectra, vibrational assignment. <...> Hartree—Fock (HF) and DFT (B3LYP) methods with the 6-311G(d,p) basis set were used in order to calculate the geometrical parameters, harmonic vibrational frequencies, and 1H and 13C NMR chemical shift values of the title crystal structure in the ground state. <...> All (C12H15Cl3O7) parameters were calculated at the HF/6-311G(d,p) and B3LYP/6-311G(d,p) levels of theory with optimized geometries. <...> These calculations are significant since they offer an insight into molecular parameters as well as IR and NMR spectra. <...> The purpose of this study is to investigate the molecular and structural parameters of the chemical behavior of the title compound and to compare theoretical approximations with experimental investigations. <...> COMPUTATIONAL DETAILS Hartree—Fock (HF) and DFT(B3LYP) [ 5, 6 <...>