Linus Pauling
Linus Pauling (28/02/1901 - 19/08/1994) Dual nobel prize winner, quantum chemist and peace activist, was one of the most prominent chemists of recent years.
http://www.nobelprize.org/nobel_prizes/chemistry/laureates/1954/pauling-bio.html
His work mostly focused on molecular structure and how bonds between chemicals react to each other. He is the only man to have won two solitary nobel prizes, without another being credited. He is also thought of as the founder of the field of quantum chemistry.