As with any undertaking that takes four years to complete, there are many people I would like to thank for their help during my studies. Firstly, I would like to acknowledge my supervisor, Prof Igor Shvets, for giving me the opportunity to join his group and allowing me to investigate these molecules despite their relative distance from his core topic. I have learned a lot from him, and I hope that he has learned something from me in return.

I would especially like to thank my Postdoc “mentor,” Dr Sergey Kransikov. Sergey basically taught me everything I know about surface science and organic macromolecules, and I would have been lost without his expertise. I wish him well in the UK and hope we can collaborate in the future. Another Sergey who was key to my studies was Dr Sergey Bozhko, whose tireless work and stimulating discussions were most illuminating.

Thank you to Dr Olaf L?ben, both for his time and effort in the lab, maintaining our cluster, and performing DFT simulations, and also for his company at lunchtimes in the Buttery. Although Dr Alexander Chaika has only been a member of the team for a short time, his input and advice have been invaluable, and I am very grateful to him. I am also grateful to Dr Tony Cafolla, both for his many insights into organic molecules, and for his experimental work in measuring the X-ray spectra of MnClTPP with Dr Krasnikov. Thanks also to the rest of the Applied Physics Group, both past and present members.

Without my other “physics” friends, Steve, Tom, Mike, Cathal and Brendan, to nerd out with and keep me sane, I don’t think I would have made it to the end. When I needed a dose of “normality” my friends from my home town of Wexford were always there for a coffee or a drink, and if I needed to be brought right back to reality, my Scouts and the other Leaders of the 13th would make sure I didn’t get too big for my boots, which we all need now and again! Thanks also to my long-suffering flatmate Dr Eric Lucking for putting up with my messiness for the past four years, and to Dr Genevieve Murray, for her advice, support and many games of Rummikub!

One of the most important people in my life for the last (almost) 3 years has been my girlfriend, Louise. She has always listened to my complaints and been the voice of reason when everything got too much for me. I’m not sure I can pay you back, but I’d like to try.

At last I get to my family. My brother Brian and his lovely wife Rhatia have been so good to me, taking me into their home, letting my play with their dog, introducing me to their friends; I don’t know where I would be without them but I know I wouldn’t be as happy.

Unfortunately my Mum didn’t get to see me complete my PhD, but I know how proud she was of me, and that she would be telling everyone she met about it.

Finally, I am so grateful to my Dad. Without his unfailing support, belief and wisdom throughout my life, I would not be the man I am today.

I dedicate this thesis to my late mother, Bernadette, and my father, Nick.
Without their support, pride and belief I would never have gotten this far.