PDF-4+ - Purchase

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Digital Experimental Patterns—New Capability

New for Release 2008 — 2,682 experimental powder diffraction entries (Source 00), that contain full digital data scans of the raw data, have been added to the database. An example is shown (above) for Zeolite A, where the data were collected and analyzed by an ICDD grantee, Stanislaw Pikus, at the University of Maria Curie-Sklodowska in Lublin, Poland. ICDD grantees have submitted raw data with their grant submissions for several years. These data are now being processed and published in PDF-4 products.

ICDD members and product users have requested the inclusion of full digital experimental patterns for several reasons. The most common reason includes using experimental patterns for total pattern analysis and pattern fitting routines for quantitative analysis. Another significant reason for adding digital experimental patterns is that they can be used as reference materials for non-crystalline, semi-crystalline and amorphous materials, which are poorly described by crystalline models, yet can display characteristic and reproducible diffraction patterns. In the case of Zeolite A (below), an experimental calculated pattern would not significantly deviate from the experimental data, because the material is crystalline. An example of deviation is shown below for the mineral, montmorillonite, a layered clay, which has been extensively studied. Here the interlayer d-spacings can vary as a function of chemical composition and specimen treatment. In addition, crystallite sizes vary from sub-micron to nano.

The experimental data above was published from the Pennsylvania State University mineral pattern collection, edited by Deane K. Smith. This historic reference was reviewed and edited, resulting in the publication of 41 clay patterns for Release 2008, including several montmorillonites, that were studied under varying experimental conditions.

Future releases will include experimental data additions with several important classes of semi-crystalline materials, such as additional clay minerals, celluloses, starches, and polymers. Data from ICDD grantees and important historic collections will continue to be added on an annual basis. Software required for storing, retrieving, viewing, analyzing and exporting these experimental data files have been added to the PDF-4 product line. PDF-4/Organics will contain digital experimental patterns with Release 2009.

More Graphics!

New for Release 2008—more graphing capabilities were added to the PDF-4 product line. Users can graph material composition (atomic or weight %) as a function of a large number of diffraction, crystallographic, chemical and physical property parameters.

The plots above were generated using 32 data points from PDF-4+ for the cell edges and data that were standardized and combined from three different database sources.

In general, four additional display fields were added in Release 2008 for a total of 70 display fields, which can be displayed and plotted with graphics having links to all entries contained in each PDF-4 product.

Additionally, our powerful interactive graphics have been interfaced allowing users to transform diffraction data from the historic stick patterns of d’s and I’s into a fully digitized pattern using on-the-fly calculation technology. You have the ability to input experimental and instrumental factors into the reference patterns enabling you to simulate a reference pattern as if it was run on your instrument. This versatile module features simulations for:

• X-ray diffraction data
• Synchrotron diffraction data
• Neutron diffraction data
• Electron diffraction data
• Electron backscatter diffraction patterns
• Electron diffraction spot patterns
  (including approximate intensities)

PDF-4+ Features

Numerous features were designed for PDF-4+ based on the addition of atomic parameters and prototype structures from the Linus Pauling File. The expanded list of features and capabilities for Release 2008 are listed here.

• Prototype Structure (alphabetical order) search - NEW
• LPF Protype Structure (alphabetical order) search - NEW
• Atomic Coordinates search
• Author’s Cell Axial Ratio search
• Graph results (X-Y plot, category plot, and histogram)
• Automatic experimental data import for known file types
• Expanded support for experimental data import file types
• Integral Index method—based on a similarity index that compares diffraction patterns to a reference, an experimental pattern can be compared to any selected set of reference patterns in the Results form.

PDF-4 and PDF-2 Product Feature Comparison

PDF-4/MINERALS 2008 - Purchase

• 29,607 minerals entries
• 6,696 mineral entries with atomic coordinates

PDF-4/Minerals is a subset of PDF-4+, which includes all of the features incorporated into PDF-4+. The database content covers >95% of all classified mineral species as defined by Fleischer’s Glossary of Mineral Species and the International Mineralogical Association. In addition to these classified mineral species, the database contains yet-to-be classified minerals, synthetics, interlayer and solid solution variants. Many common minerals have been characterized through temperature and pressure series. Overall, this results in an extensive database that contains data from four different database sources, containing 29,607 unique entries.

The data are annually peer reviewed by a task group of mineralogists. This task group assigns mineral groups and supergroups, classifications, and prototype structure types to assist users with identification and analysis. PDF-4/Minerals includes 6,145 mineral entries that have been added from the Linus Pauling File and NIST. There are 6,696 entries, which include atomic coordinates, pattern simulations and molecular graphics as described in the PDF-4+ product.

PDF-4/ORGANICS 2008 - Purchase

Download Informational Flyer

Read PDF-4/Organics Survey Results Newsletter

Designed for rapid materials identification with 370,844 entries!

New for 2009

• 1,146 new experimental entries
• 28,158 new calculated entries
• 4,371 pharmaceutical entries
• 1,722 excipient entries
• 1,900 new entries with assigned functional groups
• 974 newly flagged forensic entries (total—3,917 forensic entries)

Features

• Display of 2-dimensional chemical structure
• Data mining capability includes:
• Active Pharmaceutical Ingredients and Their Polymorphs
• Excipients and Their Polymorphs
• Pharmaceutical Salts
• Pharmaceutical Hydrates
• Drug Activity Materials
• Forensic Related Materials
• Pigments
• Common and Specialized Organic Compounds
• Organic Functional Group Index
• Ambient and Non-Ambient
• Space Groups
• Pearson Symbol Codes
• Chemical and Structural Formulae
• Chemical and Common Names
• Crystal System Related Information
• R Factors for Calculated Patterns
• Reference Intensity Ratio
• Quality Marks and Figure of Merit

PDF-4/Organics is produced, in collaboration with the Cambridge Crystallographic Data Centre, by combining drug active compounds calculated from the CSD with polymers (including starches and celluloses), common inorganic salts, excipients and pharmaceuticals from the world’s largest X-ray powder diffraction database for organics and organometallics.

Material Identification
Formulation Analysis
Quantitative Analysis
Polymorph Identification
Crystallite Size

Material Identification - polymorph screening, quality control, drug & excipients identification

The PDF-4/Organics database excels in the identification or "fingerprinting" of crystalline phases. It is designed to identify the most complex formulations. Pure organic databases do not perform well due to the common occurrence of inorganic/organic and crystalline/semicrystalline blends in commercial formulations. Unlike many databases, our database is not aligned along strict chemical definitions (i.e., exclusively organic, forensic or pharmaceutical entries). While PDF-4/Organics contains predominately organic and organometallic materials, it also contains thoU.S.A.nds of reference data for polymeric and inorganic excipients, common inorganic salts, and starting materials. We have added all the types of materials typically found as reaction products and formulation ingredients.

Formulation Analysis

Formulation analysis by X-ray diffraction is dependent on identification of each major ingredient in the formulation, followed by successive stripping of the identified material from the experimental data and reanalysis of the residual pattern to identify the next phase. Multiphase identification is only possible if you have a comprehensive database (the right phases), standardized and edited data, and high quality reference data to succeed in successive iterations of stripping and analyzing residuals.

Quantitative Analysis

PDF-4/Organics, used in combination with most vendor data analysis programs, can provide rapid semiquantitative and quantitative results. Identification can be quickly followed by quantitative analysis with the combination of the database and appropriate vendor software. The PDF-4/Organics database enables quantitative analysis by calculating I/I_c values for use by the Reference Intensity Ratio (RIR) method.

Every reference material can also be expressed as a digitized pattern. The digitized patterns can be used to do quantitative analysis by total pattern fitting techniques. In addition, every powder pattern that was derived from a single crystal analysis has a reference citation to the original article and publication, as well as the corresponding reference in the Cambridge Structural Database.

Polymorph Identification

Each polymorph contains its own signature powder pattern that is based on the changes in interplanar distances due to conformational changes. The database has a large collection of polymorphs, particularly of common commercial ingredients. The combination of single crystal data, calculated from the Cambridge Structural Database, and powder data from the ICDD in the PDF-4/Organics database results in broad coverage for most common drugs. The size and extent of the database results in thoU.S.A.nds of polymorphs. Similarly, the database contains an extensive collection of solvates, hydrates and salts.

Crystallite Size

The PDF-4/Organics database contains an interactive crystallite size calculation, useful for studying crystallite size effects in any reference material. This can be used to study and simulate nanocrystalline effects or to study the effectiveness of particle reduction techniques commonly used in the pharmaceutical industry. Digital pattern calculations can be adjusted for both instrumental and specimen factors.

Pricing is available for multiyear & site licenses.