The principles of nature are the sole foundation for ab
initio quantum chemistry: Molecular modelling methods that can accurately
predict structures, energetics, reactivity, and other features of molecules
have been created over the last two decades. Computational chemistry does not
replace experimental studies, but it does play an important role in chemists'
ability to:
Many molecular properties, such as bond energies and reaction energies,
structures of ground-excited-and transition-states, atomic charges and
electrostatic potentials, vibrational frequencies (IR and Raman), transition
energies and intensities for UV and IR spectra, NMR chemical shifts, and dipole
moment, can be computed.
This book was focused on three applications to
show the importance of quantum chemistry calculations in chemical applications
supporting experimentation.
The first application was for the electrical, chemical, vibration frequencies,
and absorption intensities of SWCNTs, which differ greatly depending on
symmetry, chirality, and diameter, necessitating experimental evaluation of
these structural parameters. The vibrational density of states, especially at
low frequencies, gives information about the structure of carbon nanotubes.
Significant differences in the frequencies and relative intensities of these
peaks provide a method for distinguishing between structurally different
nanotubes. Experiments can now yield additional structural information thanks
to our findings.
The second application involves calculating the geometrical structure, physical
properties, and inhibition efficiency parameters of new organic compounds as
inhibitors against carbon steel corrosion in acidic or basic solutions using
the quantum mechanical method of PM3 and Density Functional Theory (DFT) of
B3LYP with a level of 6-311++G (2d, 2p) in a simulated environment. The
findings were in line with the experimental percent IE. Mulliken charges
population analysis was used to investigate local reactivity. The third use
involves adopting recommended novel prodrug designs to increase active drug
solubility and thus bioavailability, increase permeability and absorption, and
change the drug's distribution profile for improved efficacy, reduced toxicity,
and adverse effects. Over time, new pharmacological therapy advances have
become increasingly complex, time-consuming, and expensive. The Gaussian 09
programme was used to execute a computational method in our prodrug design. The
total energy of the reactants was compared to the energies and transitional
stages up to the final products. The goal of the theoretical study of the
suggested primary pharmaceuticals is to see whether there are any ways to
improve the qualities of prodrugs and if there are any new alternatives to
approved prodrugs. Correlations between experimental and calculated data were
used to verify and ensure that the final results could be used.
Author(S) Detalis
Rehab Majed Kubba
Department of Chemistry, College of Science, University of Baghdad,
Baghdad, Iraq.
View Book:- https://stm.bookpi.org/AQMCSCVFCIP/article/view/3822
