M. H. Mueller (1918-1996)

Melvin H. Mueller died of heart disease June 28 1996. Mel was born February 22 1918 in Spencer, Iowa and received his PhD in Chemistry from the U. of Illinois in 1949. After several years at Deere & Co., the U.S. Rubber Co. and the U. of Illinois, he joined the Argonne National Lab. in 1960 where he was a Senior Scientist until he retired. Mel was very active in actinide structural research and published numerous papers in that field. He continued a successful collaboration with his Argonne colleagues after retirement. Among many significant contributions to powder diffraction methods, his 1960 least squares program for lattice parameter determination written with L. Heaton and K. T. Miller is still highly regarded. He collected the first set of single crystal neutron diffraction data on the CP-5 reactor, in collaboration with S. Sidhu and S. Simonsen. His knowledge of uranium phases, including anisotropic grain growth in bulk uranium, led to phase characterization of the uranium silicides. Mel also made major contributions to a variety of scientific organizations and was often a voice of reason and compassion in difficult situations. He served as Secretary of the American Crystallographic Assn (1973-1975), on the American Inst. of Physics Governing Board (1981-1987), the AIP Executive Committee (1985-1986), and on the lnt'l Centre for Diffraction Data (ICDD) Board of Directors (1991-1995). His work on the Metals and Alloys Subcommittee of ICDD resulted in the recently produced 'Metals & Alloys Search Manual' being always current and available in a most useful format. Mel chaired the Grants-in-Aid Committee of the ICDD from 1989-1993, when the number of grant recipients, especially from overseas, increased significantly. He contributed many first rate powder diffraction patterns to the Powder Diffraction File. Mel will long be remembered as a fine scientist, an enthusiastic collaborator, and a compassionate human being.