Posted: March 22nd, 2023

Introduction to Molecular Spectroscopy

What is Spetroscopy?

Spectroscopy can be defined as the study of interactions of radiation or light with matter. Molecular spectroscopy, therefore, studies and determines the degree of response of molecules interacting to various amounts of energy or frequency. Summerfield outlines various techniques used in molecular spectroscopy, which include Ultraviolet-visible spectroscopy, which measures electronic molecular absorption in solution. The fluorimeter measures absorbed radiation emitted at longer wavelengths and infrared, while Raman spectroscopy is used for measuring vibrational molecular spectroscopy. On the other hand, nuclear magnetic resonance spectroscopy measures change of spin states, while mass spectrometry measures ionization and molecule fragmentation (22).

Rovibrational Spectroscopy

For all levels of vibration, there involve rotational energy levels in respect to them. In light of this, vibrational transitions can join with rotational transitions to give rovibrational spectra, which can be analyzed to ascertain the average bond length. The core techniques in rovibrational spectroscopy are infrared (IR), Raman, and Microwave spectroscopy.

Raman Spectroscopy

Owen explains that in 1928, C.V Raman found out that the small changes that occur in the frequency of a small portion of the light scattered by molecules show the vibrational properties of the molecule (1020). In fact, the Near IR lasers made this discovery more practical by allowing for the avoidance of fluorescence in many samples.

Computational Chemistry

According to Abagyan, Computational chemistry can be described as the use of computer models to solve chemical problems such as molecular energies and structures, geometry optimizations, bonds, and orbitals, among others. It is advantageous in that it can combine experiment with theory, interpret ambiguous and conflicting results, optimize the design of experimental programs, as well as predict properties difficult or dangerous to obtain via experimentation (9).

Thermo-Nicolet FTIR

Fourier Transform Infrared is the preferred method of infrared spectroscopy. Infrared radiation is passed through a sample where the sample absorbs some infrared radiation, and some are transmitted. The end product spectrum shows transmission and the molecules absorbed. The thermo-Nicolet FT-IR is one that uses such technology.

Horiba JY MF2 Fluorimeter

The unique selectivity, sensitivity, and non-destructive nature of fluorescence spectroscopy has made it very popular in spectroscopy. The multi-frequency fluorimeter (MF2) is a milestone in fluorescence dynamics since it can obtain all frequencies-domain data in one measurement, and the Horiba JY MF2 fluorimeter is one of such.

Works Cited

Abagyan Ruben. “Computational chemistry in 25 years” Comput Aided Mol Des.26.1 (2012):9-10.

Owen A. Chris, Notingher Ioan, Hill, Robert Stevens Molly, & Hench L. Larry “Progress in Raman spectroscopy in the fields of tissue engineering, diagnostics and toxicological testing.” Journal of Materials Science: Materials in Medicine 17.11 (2006):1019-1023.

Summerfield Stephen. Introduction to Molecular Spectroscopy. Loughborough University. (2010): 1-36.