Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab®drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculatio...Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab®drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculations were performed at DFT/B3LYP and HF methods with three basis sets, namely, STO-3G, 3-21G, and 6-31G(d) in order to calculate the dipole moments of the three constituents of Flutab®drug. The Diphenhydramine compound was found to be the most stable constituent, with the lowest value of dipole moment.展开更多
Quantum chemistry calculations have been performed using Gaussian03 program to compute optimized geometry,harmonic vibrational frequency along with intensities in IR and Raman spectra at RHF/6-31++G^(**)and B3LYP/6-31...Quantum chemistry calculations have been performed using Gaussian03 program to compute optimized geometry,harmonic vibrational frequency along with intensities in IR and Raman spectra at RHF/6-31++G^(**)and B3LYP/6-31++G^(**)levels for phenobarbitone(C12H12N2O3)in the ground state.The scaled harmonic vibrational frequencies have been compared with experimental FT-IR and FT-Raman spectra.Theoretical vibrational spectra of the title compound were interpreted by means of potential energy distributions(PEDs)using MOLVIB program.A detailed interpretation of the infrared spectra of the title compound is reported.On the basis of the agreement between the calculated and observed results,the assignments of fundamental vibrational modes of phenobarbitone were examined and some assignments were proposed.The theoretical spectrograms for FT-IR and FT-Raman spectra of the title compound have been constructed.展开更多
文摘Many of the technology and computational chemistry applications are used to study drugs and their biological effects. Flutab®drug contains Paracetamol, Diphenhydramine and Pseudoephedrine. Ab-initio calculations were performed at DFT/B3LYP and HF methods with three basis sets, namely, STO-3G, 3-21G, and 6-31G(d) in order to calculate the dipole moments of the three constituents of Flutab®drug. The Diphenhydramine compound was found to be the most stable constituent, with the lowest value of dipole moment.
基金the National Natural Science Foundation of China(Grant No.10774039)the Development Program in Science and Technology of Henan Province(No.102300410114)Henan University of Science and Technology for Young Scholars(No.2009QN0032)for their support of this work.
文摘Quantum chemistry calculations have been performed using Gaussian03 program to compute optimized geometry,harmonic vibrational frequency along with intensities in IR and Raman spectra at RHF/6-31++G^(**)and B3LYP/6-31++G^(**)levels for phenobarbitone(C12H12N2O3)in the ground state.The scaled harmonic vibrational frequencies have been compared with experimental FT-IR and FT-Raman spectra.Theoretical vibrational spectra of the title compound were interpreted by means of potential energy distributions(PEDs)using MOLVIB program.A detailed interpretation of the infrared spectra of the title compound is reported.On the basis of the agreement between the calculated and observed results,the assignments of fundamental vibrational modes of phenobarbitone were examined and some assignments were proposed.The theoretical spectrograms for FT-IR and FT-Raman spectra of the title compound have been constructed.
