Isotropic H and C nuclear magnetic shielding constants of enantiometrically pure 1-trifluoromethyl tetrahydroisoquinoline alkaloids have been calculated by employing the gauge-including-atomic-orbital (GIAO) method at the B3LYP density functional level of theory. Geometry of each compound has been optimized employing 6-31G(d,p) and 6-311G basis sets. The theoretical trends are compared with exp...

In this work, a combined experimental and theoretical study on molecular structure and vibrational frequencies of (E)-3-(dicyclopropyl methylene)-dihydro-4-[1-(2,5 dimethylfuran-3-yl) ethylidene] furan-2,5-dione [DCPF] were reported. The FT-IR spectra of DCPF isomers are recorded in the solid phase. The equilibrium geometries, harmonic vibrational frequencies, thermo-chemical parameters, total ...

The aim of this research is to determine the possible solar energy storage in the norbornadiene (1) / quadricyclane (2) system, through involving steric effects on various position of carbon C1, C2 or C7 for 1 and 2; calculating the corresponding energies at B3LYP/6-311G** level of theory. The extent of the solar energy storage is the least for 11-i-Pr (-21.018), 12-t-Bu (-22.525) and 17-i-Pr (...

2-aminothiophenol and 4-methoxybenzaldehyde were cyclized under microwave irridation and solvent free conditions to synthesize 2-(4-methoxyphenyl)benzo[d]thiazole. The molecular structure and vibrational frequencies of the title compound in the ground state have been investigated with ab initio (HF) and density functional theory methods (BLYP, B3LYP, B3PW91 and mPW1PW91) implementing the standa...

The Clar aromatic sextet theory predicts that the intensity of cyclic conjugation in chevron-type benzenoid hydrocarbons monotonically decreases along the central chain. This regularity has been tested by means of several independent theoretical methods (by the energy effects of the respective sixmembered rings, as well as by their HOMA, NICS, and SCI values, calculated at the B3LYP/6-311G(d,p)...

In the title compound, C23H14N2, (I), the dihedral angle between the mean planes of the pyrene and benzimidazole ring systems is 42.08 (5)°, with a bridging C-C bond length of 1.463 (3) Å. In the crystal, mol-ecules are linked by N-H⋯N hydrogen bonds, forming columns propagating along the b-axis direction. The columns are linked via C-H⋯π inter-actions, forming slabs parallel to the ab plane. T...

The proton transfer in the isolated, mono and dehydrated forms, isolated dimers of N-Hydroxy Methylen Formamide (NHMF) have been completely investigated in the present study using Density Functional Theory (DFT), Möller-Plesset perturbation (MP2) and Hartree-Fock (HF) methods with the 6-31G and 6-311G basis sets. The barrier heights for both H2O-assisted and auto-assistance reactions are signif...

In this paper,N-(2-Fluorophenyl)-2,6-dimethyl-1,3-dioxan-4-amine (C12H16FNO2) optimized geometries and frequencies of the stationary point and energies in the ground state using DFT (B3LYP) methods with 6-311Gbasis set. The calculated HOMO and LUMO energies also confirmed that the charge transfer occurred within the molecule. Bond length and bond angles values forC12H16FNO2 were calculated by u...

Twelve H-bonded supersystems constructed between the adenine tautomers and methanol, ethanol, and i-propanol were studied at the B3LYP and MP2 levels of theory using 6-311G(d,p) and 6-311++G(d,p) basis functions. The thermodynamic parameters of the complex formations were calculated in order to estimate the exact stability of the supersystems. It was proven that the calculated energy barriers o...