Last year the international quantum chemistry community lost a kindred spirit, and a courageous and devoted practitioner. William Henry Adams, Jr. was born on December 21, 1933 in Baltimore, USA, and died of cancer on April 22, 2008 in New Orleans. He is survived by his wife, Sandra Hoffmann, daughter Maryna, stepson Thomas Hoffmann, son-in-law Jonathan Powell, and grandson Hudson Powell. Bill received great joy and comfort as a father to his family. His passing was a great shock to us, because he was so much his usual lively self at the Sanibel Symposium in 2008.
Bill Adams was the son of William H. and Mary Ellen Adams in Baltimore, USA. That he was a maverick was evidenced early on, when he got bored in his high school, dropped out, and was immediately accepted to the Johns Hopkins University. He received his A.B. in 1955. Although he did not know what a doctoral degree was as a freshman undergraduate, he quickly learned it was what he wanted, beginning graduate studies at the University of Chicago immediately after graduating. He earned his S.M. and then his Ph.D. (in 1960) under Joseph Mayer. He won a National Science Foundation Post-Doctoral Fellowship to Uppsala University, Sweden, followed by appointments as assistant professor, first at Pennsylvania State University, then at Rutgers University. Tucked in between were summer stints as a visiting scientist at Argonne National Laboratories.
Bill was tenured at Rutgers in 1969, and from that first year as Associate Professor through 1999, when he became Emeritus Professor and moved to New Orleans, he took an interest in updating the physical and quantum chemistry curricula at Rutgers to incorporate computers and practical quantum calculations. Bill mentored three graduate students: E. E. Polymeropoulos, Robert A. Vergenz (now associate professor at University of North Florida), and Meredith M. Clayton; and a postdoctoral fellow, Yasuyuki Ishikawa (now professor at the University of Puerto Rico). Bill's philosophy of graduate education was one of apprenticeship, and it was challenging to work for him, yet we learned much. Mentally, Bill easily ran ahead of his words and his students (and at times, his peers), and we found it our responsibility to slow him down and ask the questions which would make clear to us what he was thinking about.
Bill enjoyed his work, and I often heard his distinctive laugh at some joke or story around the lab, even in the midst of very hard intellectual work. Bill's good humor even saw him through great tragedy in the years after he lost his first wife in an auto accident. His work was a tonic for him in those years, and there was no pause in his productivity, even though he was frequently hurting. Bill was very congenial, able to enjoy good wine, and gathering together friends in the evening at his home a few blocks from the Wright-Rieman Laboratories. I fondly remember a party he threw to celebrate the completion of my time at Rutgers. He was an enthusiast of blues music, and quite an expert as a collector of Japanese wood-block prints.
Bill was also well-known and loved in the international community that grew up around the Sanibel Symposium, a man with great openness and a certain social flair. He first contributed to the proceedings in 1973, when the Symposium still met on Sanibel Island, and has been a regular contributor through this very year, in which his last contribution is published posthumously. From his first thesis project on the solution of the Hartree–Fock equation with localized orbitals, through his comprehensive series of articles on orbital theory, Bill was always looking to explore his subject from an angle that was fundamental. In the 1970s, he found the subject that occupied him for the remainder of his career, trying to understand the essence or minimum effects that occur when two subsystems are bonded together by electronic forces, what he called the “least distorted” solution. This was at the root of his investigations of exchange perturbation theory, his greatest contribution to quantum chemistry.
The corpus of his works is listed later, and is impressive not for its length, but for its penetrating depth. He collaborated internationally as well. Besides Uppsala, he also visited Technische Unversität, München in 1971; Technion, Haifa in 1985; and University of Oviedo, Spain in 1992. His last manuscript, in this issue of the InternationalJournal of Quantum Chemistry, clearly shows that the conventional polarization perturbation theory of intermolecular interactions cannot be expected to converge even for very weakly coupled subsystems. This conclusion also applies to all practically available implementations of exchange perturbation theory. The importance of his work consists in finding a path out of this conundrum, the path later successfully followed by other researchers.
Bill's last weeks were characteristic of his life. He spent them with his beloved wife, Sandy, and working to complete his last manuscript. There were only the beginnings of a hint that he was seriously unwell at the 2008 Sanibel Symposium. He was hospitalized shortly after returning to New Orleans, and was transferred to a hospital in Texas for more intensive treatment. When it became clear that he was in his last days, he returned with Sandy to New Orleans. One of his tasks there was to complete his manuscript and e-mail it to a colleague. This he apparently did the same day he was later found unconscious by Sandy.
Perhaps the best epitaph was given by a friend and colleague, “He simply wanted to solve important and difficult scientific problems, sometimes very difficult problems. He showed great courage, stamina, and persistence. He was not interested in solving easy problems. He was brave enough to attack the most difficult ones.” Bill devoted his life to seeking “the truth” about intermolecular interactions, and is therefore a fit inspiration to us all.