About ICDD

The International Centre for Diffraction Data® (ICDD®) is a non-profit scientific organization dedicated to collecting, editing, publishing, and distributing powder diffraction data for the identification of crystalline materials. The membership of the ICDD consists of worldwide representation from academe, government, and industry.

Our Vision - The International Centre for Diffraction Data will continue to develop tools and support the education required for materials analyses of tomorrow.

Our Mission - The International Centre for Diffraction Data will continue to be the world center for quality diffraction and related data to meet the needs of the technical community. ICDD promotes the application of materials characterization methods in science and technology by providing forums for the exchange of ideas and information.

Brief History of the ICDD
After the development of the first X-ray powder diffraction techniques in the first part of the twentieth century, the need for a central collection of diffraction patterns from known phases became apparent. Following the publication of two landmark papers in the late 1930s on the archiving and use of powder data for phase analysis by Dow scientists, the Joint Committee for Chemical Analysis by Powder Diffraction Methods was founded in 1941. They produced a primary reference of X-ray powder diffraction data, which became known as the Powder Diffraction File™ (PDF®). This effort was initially supported by Committee E-4 of the American Society for Testing and Materials (ASTM). Over the next two decades, other professional bodies added their support, culminating in 1969 with the establishment of the Joint Committee on Powder Diffraction Standards (JCPDS). The JCPDS was incorporated to continue the mission of maintain the PDF. In 1978, the name of the organization was changed to the International Centre for Diffraction Data in order to highlight the global commitment of this scientific endeavor.

The ICDD Organization
Approximately 300 scientists from around the world comprise the active membership from which the organization draws its Board of Directors, committees, and subcommittees. The members, who are volunteers, are actively engaged in developments in the field of X-ray powder diffraction and related disciplines. Membership consists of scientists from various affiliations - educational, governmental, and industrial. An annual meeting of the members provides a forum for the exchange of ideas and information pertinent to the scientific community and to organize, plan, and review policies and procedures within the ICDD organization. A paid scientific and administrative staff, located at the Newtown Square, Pennsylvania Headquarters, is responsible for the production and distribution of the various databases offered by the ICDD.

The Ludo Frevel Crystallography Scholarship Fund
The International Centre for Diffraction Data (ICDD) has established a crystallography scholarship fund to encourage promising graduate students to pursue crystallographically-oriented research, now known as the Ludo Frevel Crystallography Scholarship Fund. Its name was adopted to honor a pioneer in the science of X-ray diffraction, and the founder of the fund, Dr. Ludo Frevel. Convinced of the beneficial scientifc impact of the proposed scholarships for crystallographically-oriented research, the ICDD has solicited funds from private and industrial sector to support this program. To date, the ICDD has awarded 191 scholarships since 1991, totaling over $454,750. Please contact Stephanie Jennings (sjennings@icdd.com) for further information.

The Powder Diffraction File ™
The Powder Diffraction File™ (PDF®) is a collection of single-phase X-ray powder diffraction patterns in the form of tables of characteristic interplanar spacings and corresponding relative intensities along with bibliographic, physical and crystallographic properties. The creation, maintenance, and dissemination of such a file was the primary purpose for the establishment of the ICDD and its predecessor organizations.

In order to meet the individual needs of diffractionists worldwide, the Powder Diffraction File™ is available on a variety of media - books, CD, and DVD. The PDF has various subfiles of data which include, but are not limited to, minerals, metals and alloys, and forensic materials. There is also an educational package for classroom use. Various methods, including the use of printed indexes and computer software, enable users to match data in the File with their laboratory data.

Data Acquisition for the PDF ®
Data for the publication in the Powder Diffraction File™ are acquired through contributions from individual scientists, corporate laboratories, literature surveys, and a Grant-in-Aid program . Approximately 200 leading scientific journals are searched manually for powder diffraction data and thousands are searched by key word searches. Additional literature surveys covering patents, dissertations, and the remaining open literature are performed utilizing various online databases and search techniques. The Powder Diffraction File cites over 1.3 million references.
Data are also acquired through a series of historic collaborative agreements with international database organizations. These include the National Institute of Standards and Technology (NIST), Fachinformationszentrum (FIZ), Cambridge Crystallographic Data Centre (CCDC), and Material Phases Data System (MPDS).

PDF Quality Assessment
All data are critically reviewed and evaluated by the editorial staff. Each pattern must pass through a four-tiered editorial review process before it can be included in the PDF. As technology evolves, the quality requirements for reference pattern data also evolve. As a result, information in the PDF is continuously reviewed and upgraded for accuracy and quality.