planetary-science-2018-posters-abstracts

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Journal of Astrophysics & Aerospace Technology | ISSN: 2329-6542 | Volume 6

Planetary Science and Particle Physics

International Conference on

August 27-28, 2018 | Boston, USA

Computational assignment of vibrational frequency bands facilitates the identification of Raman spectra

Pardis Tabaee Damavandi

Queen Mary University of London, UK

pectroscopic parallax is the measure of the distance between two stars or celestial objects and relies on the stellar spectral type

and luminosity class defined by the Morgan-Keenan classification system. UV, IR (infrared), Raman or optical spectrographic

instruments are ‘integrated’ in many telescopes and are used to obtain information on brightness, temperature (surface), density and

velocities. Stars are classified based on their type and on their brightness, which allow us to obtain distances to them, however, with

previous classification systems, the star’s size, i.e. dwarf, giant or supergiant and composition (heavy metal versus carbon stars) were

also used. The Morgan-Keenan classification offers information on the star color, i.e. very blue and the type, however, the infrared

wavelengths are approximately >9000 Å. We therefore tend to speak of near-infrared spectra. Spectra can be ulterior division into

continuous, band and linear. Band spectra are usually descriptive of molecular compounds and are the ones that we investigated. We

are going to concentrate on the interpretation of Raman band spectra of a small biological peptide, i.e. human glutathione (GSH),

but we the same approach can be applied to gain stellar information. Our method consisted in using vibrational dynamics (VD), the

study of atomic oscillations within a molecule. We previously obtained experimental vibrations for the peptide through Raman or

IR spectroscopies available in the literature. These techniques have been widely used in the past, but the assignment of vibrational

frequency bands is still challenging. In recent years, researchers have used ab initio and other computer simulation methods that

facilitate band recognition. The goal of this work was to apply computational vibrational dynamics studies to the structure of human

glutathione, and to then compare these values with its IR and Raman frequencies. By analyzing both simulation results and by

comparing them with empirical data, we gained important information about the vibration modes of glutathione. This study showed

that some bands that may not be visible in Raman or IR spectra can be 'detected' with this technique. Furthermore, our findings

illustrate that most peaks obtained experimentally match those achieved in the computational simulation. Vibrational dynamics was

therefore not just effective in understanding the structure of glutathione, but it can also be used to refine the quality of experimental

Raman-IR data.

J Astrophys Aerospace Technol 2018, Volume 6

DOI: 10.4172/2329-6542-C2-021