Glenn T. Seaborg Award for Nuclear Chemistry

Sponsored by the ACS Division of Nuclear Chemistry & Technology

Romualdo T. de Souza, the son of an American oil company engineer, was born in India in 1963. When he was six, his family relocated to Dubai, United Arab Emirates, where they lived for four years before immigrating to the U.S. De Souza grew up in the late 1960s, and his passion for science and engineering was ignited by the Apollo space program and the race to put a man on the moon.

De Souza, professor of chemistry at Indiana University, Bloomington, is now a leading researcher in the field of nuclear reaction dynamics. The award winner has been selected for his work in elucidating the nature of nuclear multifragmentation through the use of fragment-fragment velocity correlations and developing key instrumentation enabling research in nuclear chemistry.

"Professor de Souza is a true scholar doing cutting-edge research in the field of nuclear chemistry," says David E. Clemmer, Robert & Marjorie Mann Chair of Chemistry at Indiana University. "The insight, ambition, and energy that Professor de Souza brings to his science are remarkable," Clemmer says.

Receiving this honor, however, was a bit of a surprise for de Souza. "It is gratifying to have the work that you feel so passionately about recognized by colleagues in the field," he says. He adds that winning this award is particularly meaningful as many of his scientific role models are former Seaborg Award recipients.

De Souza's research deals with nuclear reactions involving a single collision of two nuclei. The collision yields a highly excited nuclear system that rapidly decays into multiple protons, neutrons, and larger clusters. This phenomenon is known as multifragmentation.

"This technique of fragment-fragment correlations utilizes the interaction between the particles themselves to assess the spatial and temporal extent of the decaying source on the timescale of less than 10^-21 seconds," de Souza explains. With this approach, his group has been able to show that multifragmentation is an evolutionary process and does not involve an instantaneous breakup of a highly excited system into multiple fragments as previously thought.

De Souza's research also included the development of sophisticated instrumentation capable of yielding high isotope and angular resolution. Specifically, he has played a key role in developing 4π detectors and silicon strip arrays.

In addition to his research contributions, de Souza has been active in improving chemical education. For example, in 1996, he developed the Computer Assisted Learning Method (calm.indiana.edu), which is a Web-based learning environment that is now being used by more than 2,000 first-year chemistry students at Indiana University's Bloomington campus.

"Professor de Souza brings to his research an energy and intellect that has enriched not only our knowledge of the interactions between complex nuclei but also the broader scientific community through his initiatives in instrumentation and chemical education," says Claus-Konrad Gelbke, director of the National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University.

Prior to joining Indiana University in 1991, de Souza, 44, completed a postdoc appointment at the University of Rochester and a research assistantship at NSCL. He holds Ph.D. and M.S. degrees from the University of Rochester (1988 and 1985, respectively) and an A.B. from Washington University, St. Louis (1983).

De Souza was an SBC Fellow in 2003 and an Ameritech Fellow in 2002. He is a member of ACS, the American Association for the Advancement of Science, the American Physical Society, and Sigma Xi.

The award address will be presented before the Division of Nuclear Chemistry & Technology.