Updated August 14, 2012
A. Welford Castleman, Jr., received a B.Ch.E. from Rensselaer Polytechnic Institute in 1957 and his Ph.D. (1969) degree at the Polytechnic Institute of New York. He has been on the staff of the Brookhaven National Laboratory (1958-1975), Adjunct Professor in the Departments of Mechanics and Earth and Space Sciences, State University of New York, Stony Brook (1973-1975), and Professor of Chemistry and Fellow of CIRES, University of Colorado, Boulder (1975-1982). In 1982 he accepted a professorship in the Department of Chemistry at The Pennsylvania State University, and was given the distinction of the Evan Pugh Professor title in 1986. In 1999 Professor Castleman was appointed Eberly Distinguished Chair in Science, and a joint professor in the Department of Physics. He has been a member and on the Advisory Board for The Penn State Particulate Materials Center, and is currently a member of the Materials Research Institute.
Professor Castleman was elected a Member of the National Academy of Sciences in 1998, a Fellow of the American Academy for Arts and Sciences in 1998, and a Fellow of the New York Academy of Sciences in 1998. He received the Wilhelm Jost Memorial Lectureship 2000 Award from the German Chemical Society (Bunsen-Gesellschaft fuer Physikalische Chemie), was a Fulbright Senior Scholar in 1989, the recipient of the 1988 American Chemical Society Award for Creative Advances in Environmental Science and Technology, awarded a Doktors Honoris Causa from the University of Innsbruck, Austria in 1987, named a U.S. Senior Scientist von Humboldt Awardee in 1986, 1996, and 2007, elected a Fellow of the American Association for the Advancement of Science (1985) and the American Physical Society (1985), a Senior Fellow of the Japanese Society for the Promotion of Science in 1985 and 1997, and a Sherman Fairchild Distinguished Scholar at Cal Tech in 1977. He received the Rensselaer distinguished alumni award, the Thomas W. Phelan Fellows Award in 2007. In 2010, Castleman received the Irving Langmuir award in Chemical Physics from the ACS.
Welford Castleman served as Editor-in-Chief of a Springer Verlag book series on Cluster Physics and now serves as a coeditor of their book series in Chemical Physics. He was a Senior Editor of The Journal of Physical Chemistry for ten years (1988-1998), a Coeditor of Zeitschrift Für Physik D, and has served on numerous journal editorial boards including NanoLetters, The Journal of Physical Chemistry, Chemical Physics Letters, Advances in Chemical Physics, Research Trends, and Understanding Chemical Reactivity (Reidel Series), The Journal of Chemical Physics, The International Journal of Mass Spectrometry and Ion Processes, The Journal of Atmospheric Chemistry, and Aerosol Science and Technology. Professor Castleman has organized a number of national and international conferences, most recently Femtochemistry VII, and organized the first European Gordon Conference in 1990, serving as Chairman of the Conference on Molecular and Ionic Clusters. He has served on a number of advisory committees for governmental agencies and as a consultant to E. I. DuPont de Nemours. He was a member of the NAS-NRC Board on Chemical Sciences and Technology for 6 years, and was co-chair for 2 years until 2006.
Professor Castleman is engaged in studies to bridge the gas and condensed phase through investigation of the dynamics of formation, the laser photophysics and spectroscopy, and the reactions and bonding of gas-phase clusters. He is particularly interested in exploring the properties of matter of finite dimension, elucidating through cluster research: solvation phenomena and its influence on reactivity, the dynamics of reactions in systems of restricted size using ultrafast laser techniques, the physical basis for catalysis and surface phenomena at the molecular level; and investigating the unique characteristics of clusters as building blocks to cluster assembled nanoscale materials. In 1992 he reported the discovery of a new class of molecular clusters termed metallocarbohedrenes, or Met-Cars for short, and more recently demonstrated along with a collaborator that clusters, termed superatoms, could be assembled which mimic elements of the periodic table. In 1997, he developed a unique method of arresting intermediates in chemical reactions employing a Coulomb explosion femtosecond laser technique. He has over 600 publications.