Motivation letter for PhD

hi everybody i have been trying to write a motivational letter for PhD stating research interest and professional goals in chemistry since last two weeks. plz help me with it. here is what i have been able to write till now.

xxxxxx School of Chemistry,
University of xxxxx.
xx xxxx 2012

Dear Members of the Selection Committee,
I am writing to apply for the PhD program at your university for the session starting in October 2012.
I graduated in Industrial Chemistry with First rank from xxxx University. After completing my graduation I joined M.Sc. (Organic Chemistry) at xxxx university and passed M.Sc. with first Class in April 2011. Having strong desire to work in challenging field of chemistry and wanting to work on something helpful to the scientific community and humanity I joined xxxxxx Pharmaceuticals as a Junior Research Associate in R&D dept.
As a postgraduate student at xxxxx University I gained a concrete knowledge in theoretical as well as practical aspects of Organic Chemistry. Especially the Laboratory sessions of Multistep organic synthesis, Photochemical reactions, Microwave assisted reactions, Natural product extractions & Chromatographic separation methods developed a great deal of laboratory skills and provided me with enthusiasm and zeal to work in the field of Organic Chemistry.
During my working experience as a Junior Research Associate at xxxxxxx Pharmaceuticals I came across some of the many difficulties faced during Organic synthesis. Troubleshooting such difficulties & looking for alternative process through literature search in case problem was not solved, gave me a good learning experience and developed me as a strong organic chemist. Also working in a team during the Process Research and Development of Active Pharmaceutical Ingredients (API’s) developed in me a good amount of team working and interpersonal skills.
Main Challenge during the synthesis was of the enantiomeric purity required of some of the API’s. For achieving enantiomeric purity we resolved the intermediates synthesized during the process and further purified it which led to yield losses. I would like to work in the field of Asymmetric synthesis & Chiral pool synthesis which would lead to a single enantiomer in good enantiomeric purity (ee) and yield. Developing catalysts (Homogenous & Heterogeneous) for such synthesis would be challenging & a rich learning experience. Ultimately I would like apply such catalyst for Organic synthesis especially Natural Product Synthesis. I am looking forward to pursue PhD in a challenging and competitive environment of Organic Chemistry and would later join a university for further research.

I would like to join the xxxxx School of Chemistry because of the outstanding educational system, excellent facilities, novel, active and quality research done in the field of organic chemistry. With many experienced Professors, I know I will gain Knowledge at the fore front of discovery. Moreover my theoretical knowledge and Industrial Research experience would allow me to pursue cutting edge research in field of Organic Chemistry.
I am confident that I will bring high level of energy and enthusiasm to your program. I am sure of exceeding your expectations because of my academic knowledge as well as industrial working experience and team working skills. Furthermore my international background and interdisciplinary education will add more diversity to your program.
Thanking you for considering my application and I look forward to your positive response.

Plz... someone help me out with this letter.......