American Crystallographic Association
The American Crystallographic Association, Inc. (ACA) is a non-profit, scientific organization for scientists who study the structure of matter via crystallographic methodologies. Since its founding in 1949 it has amassed over 2000 members worldwide. The association meets annually in July and has several interest groups dealing with specific aspects of crystallography, including fiber diffraction, neutron scattering and powder diffraction. A quarterly magazine, called "ACA RefleXions", is published in addition to a scholarly journal. "Structural Dynamics" is a peer-reviewed, open access, online-only journal co-published by ACA and AIP Publishing. It highlights research articles on  structural determination and dynamics of systems, enabled by the emerging new instruments (e.g. XFELs, high harmonic generation, ultra-short electron sources, etc.) and new experimental and theoretical methodologies. The journal is accepting short communications, topical reviews, and research papers in the following topics: Experimental Methodologies, Theory and Modeling, Surfaces and Interfaces, Materials, Liquids and Solutions, and Biological Systems. The association presents several awards Past presidents. Past presidents of the association include: