The primary objective of this U.S.-Czechoslovakia research project between Dr. Daniel Litvin of Pennsylvania State University and Dr. Vojtech Kopsky of the Czechoslavok Institute of Physics is to develop a systematic, unified theory for defining relationships among subperiodic subgroups of crystallographic space groups. There exists a wide variety of nomenclature and notation for these groups, i.e., Frieze groups, ribbon groups or line groups in two-dimensions, and rod groups, linear space groups or one-dimensional (subper- iodic) groups in three-dimensional space. But no complete standards exist for the subperiodic groups in the International Tables for Crystallography. The researchers intend to set the standards for the orientation of axes and origins of the subperiodic subgroups of the space groups to replace the myriad of choices found in the literature. Their efforts should yield a useful, standardized reference for classifying and characterizing subperiodic groups by their irreducible qualities. Such a work should be an important contribution to the infrastructure of the research communities examining topics in condensed matter and materials science. This project in condensed matter theory fulfills the program objective of advancing scientific knowledge by enabling leading experts in the United States and Eastern Europe to combine complementary talents and pool research resources in areas of strong mutual interest and competence.
