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The Schiff base compound, C12H7N2O2F3S, has been synthesized and characterized by IR, UV-Vis, 1H-NMR, 13C-NMR and single-crystal X-ray diffraction (XRD) and elemental analysis. The compound, an Ortep-3 [1] view of which is shown in Fig. 1, crystallizes in the monoclinic space group P-1 with a= 7.5700(11) Å, b= 12.8280(16) Å, c= 13.0170(16) Å, α= 89.295(10)o, β= 88.691(11)o, γ= 82.246(11)o and Z=4 in the unit cell. The molecular structure is stabilized by C-H...O and C-H...F intramolecular hydrogen bonds and molecules are linked through intermolecular C-H...O and C-H...F type hydrogen bonds and C-H...Cg (π-ring) interaction. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartre-Fock (HF) and density functional theory (DFT/B3LYP) [2] with 6-31G(d) [3] basis set. The results of the optimized molecular structure are exhibited and compared with the experimental X-ray diffraction. To determine conformational flexibility, molecular energy profile of the title compound was obtained by B3LYP with the 6-31G(d) basis set calculations with respect to selected degree of torsional freedom, which was varied from –1800 to +1800 in steps of 100. In addition, molecular electrostatic potential (MEP) distribution and frontier molecular orbitals (FMOs) properties of the title molecule were investigated by theoretical calculations at the B3LYP/6-31G (d) level. Figure 1. Ortep 3 diagram of the title compound. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
abstracts
Experimental and DFT studies of (Z)-N-[3- Methoxy -5-(trifluormethyl) phenyl]-1-(5- nitrothiophene -2- yl)methanamine Tufan Akbala, , Erbil Aǧarb, Sümeyye Gümüşb and Ahmet Erdönmeza aDepartment of Physics, Ondokuz Mayıs University, Samsun, Turkey . b Department of Chemistry Ondokuz Mayıs University, Samsun, Turkey E-mail: erdonmez@omu.edu.tr The title molecule, C13H12N2O3F3S, is nonplanar with an interplanar angle of 23.94(23)0 between the benzene and thiophene rings. In the crystal there exist only weak intermolecular C–H...O interactions and π...π interactions between the benzene rings and thiophene rings [centroid–centroid distance= 4.892(3) A0]. The length of the C9=N2 double bond is 1.2534 A0. This value agrees well with the analogous bond reported elsewhere. [1,2]. The theoretical calculations were performed with Gaussian03W software. In calculations, the stable structure geometries of the isolated molecules in the gas phase was investigated under the framework of Density Functional Theory (DFT). In order to find the stable molecular geometries, the global minimum scanning were performed on the potential energy surfaces and some properties of molecules such as charge densities, dipole moments and frontier orbitals (HOMO and LUMO) from B3LYP/6-31G(d) calculations. REFERENCES: [1] Akbal T., Aǧar E., Erdönmez A., 2012. Acta Cryst. E68, 2673. [2] Aygün M., Işık Ş., Öcal N., Nawaz T.M., Kaban Ş. & Büyükgüngör O., 1998. Acta Cryst. C54, 527-529. Keywords: tautomerism, crystal and molecular structure, density functional theory(DFT) studies
