N-(Chloromethyl)phthalimide

The Fourier Transform Infrared (FT-IR) and FT-Raman of N,N-diethyl-4-methylpiperazine-1-carboxamide (NND4MC) have been recorded and analyzed. The structure of the compound was optimized and the structural characteristics were determined by density functional theory (DFT) using B3LYP method with 6-31G(d,p) and 6-311G(d,p) basis sets. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. The theoretically predicted FT-IR and FT-Raman spectra of the title molecule have been constructed. The detailed interpretation of the vibrational spectra has been carried out with aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology. Stability of the molecule arising from hyperconjugative interactions and charge delocalization has been analyzed using natural bond orbital (NBO) analysis. The results show that electron density (ED) in the σ(*) and π(*) antibonding orbitals and second order delocalization energies (E2) confirm the occurrence of intramolecular charge transfer (ICT) within the molecule. The electronic dipole moment (μD) and the first hyperpolarizability (βtot) values of the investigated molecule were computed using Density Functional Theory (DFT/B3LYP) with 6-31G(d,p) and 6-311G(d,p) basis sets. The calculated results also show that the NND4MC molecule may have microscopy nonlinear optical (NLO) behavior with non zero values. Mulliken atomic charges of NND4MC were calculated. The (13)C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results. The UV-Vis spectrum of the compound was recorded. The theoretical electronic absorption spectra have been calculated by using CIS, TD-DFT methods. A study on the electronic properties, such as HOMO and LUMO energies, molecular electrostatic potential (MEP) were also performed.

Quantum mechanical calculations of energies, geometries and vibrational wavenumbers of 6-aminopenicillanic acid were carried out by using ab initio HF and density functional theory (DFT/B3LYP) methods with 6-311G(d,p) basis set. The optimized geometrical parameters obtained by HF and DFT calculations are in good agreement with experimental X-ray data. A detailed interpretation of the infrared spectra has also been reported. The theoretical IR and Raman spectrograms have been constructed and compared with the experimental FT-IR and FT-Raman spectra. The differences between the observed and scaled wavenumber values of most of the fundamentals are very small. The thermodynamic parameters have also been computed.

Quantum mechanical calculations of energies, geometries and vibrational wavenumbers of 2,4-diamino-6-hydroxypyrimidine (2,4DA6HP) were carried out by using ab initio HF and density functional theory (DFT/B3LYP) method using 6-311G(d,p) basis set. The optimized geometrical parameters obtained by B3LYP method show good agreement with experimental X-ray data. The best level of theory in order to reproduce the experimental wavenumbers is B3LYP method with the 6-311G(d,p) basis set. The difference between the observed and scaled wavenumber values of most of the fundamentals is very small. A detailed interpretation of the infrared spectra of 2,4DA6HP was also reported. The calculated HOMO and LUMO energies show that charge transfer occurs in the molecule. The entropy of the title compound is also performed at HF/6-311G(d,p) and B3LYP/6-311G(d,p) levels of theory. The theoretical spectrograms for FT-IR and FT-Raman spectra of the title molecule have been constructed.