Arba Minch 9-9-2013
A seminar on chemistry on Organic compounds Structural Elucidation by joint spectroscopy methods took place in Arba Minch University main campus. Mr. Addis Salem Abebe of Organic Chemistry has dealt with subject as how to we find correct organic compounds structural elucidation and gave succinct explanation to it.


Structure determines in Organic compounds relies on instrumental methods and several depend on absorption of electromagnetic radiation. Spectroscopy means initiation of matter with energy and different spectroscopic techniques are available. 
While Ultra violet spectroscopy deals with electron distribution, Infra red spectroscopy reveals presence or absence of key functional groups. Nuclear Magnetic Resonance tells about carbon & Hydrogen frame work in the compound
Principle of molecular spectroscopy is E2-E1 or E and Nuclear Magnetic Resonance uses two different spin states while Infra Red spectroscopy uses vibrational energy states and Ultra violet uses different electronic energy states.  Spectrometers are designed to measure absorption of electromagnetic radiation, Mr. Addissalem  Abebe   said.
He has also stated that the relationship between molecular formulas principle bonds and rings is referred to as the index of hydrogen deficiency
Infra Red Spectroscopy
Electromagnetic radiation in the 4000-625cm-1 region corresponds to the separation between adjacent vibrational energy states in organic molecules.  He has shown types of molecular vibrations and CO2vibational modes as well
Nuclear Magnetic Resonance Spectroscopy
Nuclear magnetic resonance spectroscopy depends on the absorption of energy when nucleus of an atom is excited from its lowest energy spin state to the next higher one.   He has said that two elements that are most common in organic molecules are carbon and hydrogen.   .
Mr. Addisalem further says that the induced magnetic field of the electrons in the carbons-hydrogen bond opposes the external magnetic field.  The dependence of the resonance position of a nucleus that results from its molecular environment is called its chemical shifts.   Chemical shifts of representative types of protons and interpreting proton NMR spectroscopy have been explained by him.
Mr. Addissalem Abebe solved chemical  problems in a  seminar participated by students and others.
S. Ganesh