Abstract:
Raman Effect originates from the inelastic scattering of light, and it can directly probe
vibrational states in molecules and materials. The Electromagnetic fields of the
incident radiation polarizes the charges of the molecule leading to the creation of an
oscillating electric dipole. The scattered light has modified frequencies called Stokes
and anti-Stokes frequencies. However, many theories that attempt to describe the
existence of modified frequencies cannot account for the effects of the changes of
electromagnetic and oscillating electric fields on these frequencies. This study sought
to develop a theory that explains the effects of the oscillating electric field created by
the oscillating dipole on the Stokes and anti-Stokes lines and their application in
predicting cancerous cells. The objectives of this study were to formulate a theory
that leads to determination of additional Raman frequency from the effects of
electromagnetic fields on oscillating electric dipole; to develop a dataset of the
frequencies of modified Stokes and anti-Stokes lines in the Raman scattering for some
polar molecules: to examine and explore how Raman dataset and machine learning
tool can be used in predicting cancerous cells. A theoretical model was formulated by
calculating the energy due to the oscillating electric field created by the oscillating
dipole using electrodynamics principles. The parameters needed were investigated by
applying some approximations on the theory of retarded potentials, and then Maxwell
equations were used to deduce the expression of oscillating electric fields. The
frequency corresponding to the energy due to this field will determine the modified
frequencies of Stokes and anti-Stokes lines. The dataset was generated, analyzed, and
applied in machine learning tool to predict cancer cells. It is indicated from the results
that the frequency difference in the peaks of modified Raman lines of molecules with
high dipole moments ranges from 4.0x1014s
-1
to 9.0x1014s
-1 and less than 1.0x1014s
-1
for less polar molecules. Based on the theory electromagnetic fields and oscillating
electric fields, there are differential modified Raman frequencies data which can be
used to distinguish the normal and cancerous cells with 96.75 % accuracy The study
concludes that electric fields created by the oscillating electric dipole results to Raman
scattering with modified frequencies which are sensitive to chemical structure of a
molecule and these can be used to predict the presences of cancerous cells .The theory
developed gives a formula that presents new results related to light matter interactions
and allows a detailed description of Raman scattering. The law of conservation of
energy validates the theory developed although actual experimental studies in future
may be able to decide how far it will be a reliable technique