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The focus of the Farley Lab is molecular ion spectroscopy. Spectroscopy is the study of energy level structures in atoms and molecules. Atoms and molecules absorb and emit light at specific frequencies and energies. These frequencies define the atom?s absorption and emission spectrum. The study of these energy level structures can yield an understanding of the geometrical and chemical properties of the atoms and molecules. This is important for a variety of sciences, including molecular astronomy, chemistry, and materials science.

I am currently working on a project for Dr. Farley involving the recovery of spectroscopic data of negative ions. Negative ions are a critical quantity in the physics and chemistry of many plasmas including the earth?s atmosphere, the sun's photosphere, and play a role in the chemistry of the interstellar medium. They are very reactive and important for understanding the chemistry of the medium they are in.

The spectroscopic structure of molecules can be broken up by energetic analysis at different scales using the Born-Oppenheimer approximation, corresponding to electronic transitions in the visible and ultraviolet, vibrational transitions in the infrared, and rotational transitions in the far infrared and microwave regions.

The spectroscopic data I am charged with is vibrational/rotational transitions of the nitroxide ion, HNO-. The geometry of this molecule is very close but not quite linear. In these transitions are observed a curious effect, an asymmetry splitting caused by the slight deviation of HNO- from being a true prolate top. Measurement of this splitting can yield information about the bond lengths and bond angles of the anion.

It is thought that the two isotopes H14N0- and H15NO- have the same bond angles and bond lengths. However, the data in question have larger than expected disparities between the two isotope?s asymmetry splitting. This poses an interesting problem for theorists.

In order to be sure of this disparity, knowledge of the error in the splitting due to noise is needed. Unfortunately, the data in question was taken with a strip chart recorder that did not resolve the data into digitized points, needed for a thorough analysis of the error.

I have written an original program that recovers digitized data from hard copy strip chart recordings. This program plots the image received through a high resolution scanner in raw format and transforms the image into a curve of singular line width. The program then extracts coordinate information from the line, creates a single variable function, digitizes the data, and writes it to a standard ascii file for later processing and analysis. The program has been written and compiled in Microsoft QuickBasic.

The program is especially good at and made to extract coordinate information from noisy curves laid down on strip chart recordings that feature "non-singular line width", i.e.... ink bleeding. The program will be used to recover information from a hundred or so recordings to measure the asymmetry splitting and the uncertainty in the splitting, of the infrared vibrational/rotational spectrum of HNO-.