This is a past event.

John Jaszczak from Michigan Tech University will present at this week's Physics Colloquium. Dr. John Jaszczak's presentation is titled "Wanted! Criminal Minerals (For Breaking the Laws of Crystallography)".

The seminar will be presented  at 4:00 p.m. on Thursday (Sep.17) in Fisher 139. The coffee hour will be held at 3:30 in the Fisher Hall Lobby.

Abstract The laws of classical crystallography have been well established for hundreds of years and are immensely successful in science and technology. As naturally occurring crystalline materials, minerals are subject to the laws of crystallography too. But thanks to entropy and countless complicating factors provided by dynamic geological contexts, minerals break the laws of crystallography routinely- and sometimes profoundly. This exhibit briefly reviews the fundamental law of classical crystallography – that all the atoms in a crystal are arranged in a perfectly periodic fashion- and highlight some of the implications. A selection of example mineralogical lawbreakers is described. These range from minor infractions like impurities and defects, to repeat offenders like twinned crystals, and finally to the fundamentally incorrigible, yet fascinating, examples of incommensurate crystals and quasicrystals. Find out if the lawbreaking minerals are guilty or not. To help illustrate many of the concepts, a variety of fun, helpful and probably surprising examples will be used.

Bio Dr. John Jaszczak is Professor of Physics at Michigan Tech, where he has taught and conducted research since 1991. He is also the Director and the John & Phyllis Seaman Endowed Curator of Michigan Tech’s A. E. Seaman Mineral Museum. His childhood love of minerals inspired him to become a scientist. He earned his B.S. degree in Physics from Case Western Reserve University, and his M.S. and Ph.D. degrees in Physics from Ohio State University. Subsequently he did computational research at Argonne National Laboratory for two years as a postdoctoral appointee. Jaszczak’s interest in incommensurate “Criminal Minerals” stems from his early research on quasicrystals, and more recently from the study of the new mineral merelaniite that he helped describe in 2016. The mineral jaszczakite was named in his honor by L. Bindi and W. Paar in 2016.