PDF-4+
PDF-4+ - Purchase
Identify and Quantitate
Use the combined power of 4 databases
- 272,232 Data Sets with Digital Patterns
- 181,661 Data Sets with I/Ic
- 107,507 Data Sets with Atomic Parameters
48 Searches
66 Data Field Selections
Identify
PDF-4+ combines the world's largest sources of inorganic materials data in a single, easily searched database. The combination of data from ICDD, MPDS, NIST and FIZ provides a comprehensive collection of inorganic, bibliographic, diffraction, physical property, and crystal data. Designed for problem solving and material identification, the database also includes common organic and polymeric materials for practical phase identification.
Quantitate
PDF-4+ enables three methods for quantitative analysis.
Quantitate your results using:
1) digital patterns as input to pattern fitting methods,
2) I/Ic for the Reference Intensity Ratio (RIR) method, or
3) atomic parameters for input into Rietveld refinement.
In addition, ICDD software distributors have interfaced their software packages with PDF-4+, enabling rapid automated identification and quantitation using these three methods.
The inclusion of the Linus Pauling File (LPF) provides PDF-4+with the added dimension of a large collection of data with atomic parameters, structural classifications, molecular visualization, and bonding.
Every entry in PDF-4+ can be viewed as a digitized pattern. Three separate algorithms are utilized for data simulations depending on the type of data contained in the PDF entry. Digitized pattern simulations are calculated on-the-fly and are interactive. Drop down menus allow the user to select a wide variety of radiation wavelengths and sources (X-ray, neutron or electron), instrumental optics, specimen conditions, and peak profiles. Crystallite sizes can be simulated for thin film and nano-materials analyses.
The diversity in simulations is shown in the above two figures, one of which demonstrates microcrystalline cellulose and the other simulates data taken with synchrotron radiation. These pattern simulations demonstrate > two orders of magnitude in the FWHM with different wavelengths and optical geometries between the two experiments. The 10-phase simulation used data from three different database sources.
The versatility of the simulation software provides the user with the ability to simulate a wide variety of materials under various experimental and specimen conditions.
More Data for Identification
PDF-4+ continues to grow with annual updates from the bibliographic efforts of the ICDD, FIZ, and MPDS. Release 2007 contains 17,359 new entries and 9,216 additional entries with atomic coordinates.
Specific editorial efforts were focused on common materials such as minerals and cements. Crystal structures from ICDD grants have also been added, including the structures of three known polymorphs of cellulose, one of the world’s most common natural materials.
Subfile Enhancements
In PDF-4+, over 48,000 new subfile classifications were added this year, expanding the subfile system by 28%. In addition, the majority of new assignments are from entries based on singlecrystal data, most of these have I/Ic values and many have atomic coordinates. The large growth in the subfiles for Release 2007 is a result of the improved classification and editorial review system. Overall, this editorial update should result in more efficient and accurate identifications and improved quantitative analysis.
More Quantitation—Quality Marks and Cross-References
Accurate quantitative results depend on using the best available reference data. The Powder Diffraction File is a standardized, edited database and the only global structural database that includes a quality analysis and assessment with every entry. Common minerals, inorganic oxides, and commercial materials have multiple entries in the PDF. The selection of the appropriate reference among several choices can make or break a quantitative analysis.
PDF-4+ contains the following:
- All entries have quality marks
- 79,375 entries with alternate cross-references
- 39,190 entries with primary cross-references
- 201,940 editors comments on quality assessment
- 25,293 experimental patterns referenced to structures
The combination of cross-references and quality marks has been used to direct users to the highest quality data available for accurate quantitation. Emphasis has been placed on data entries of primary patterns with star quality. The former is based on the most representative room temperature reference and the latter is based on a statistical analysis of the data quality (i.e., crystallography matches, chemistry matches, physical properties). ICDD’s editors, consulting editors and editorial task groups are field experts that review these assignments.
Data Mining and Plotting!
PDF-4+ is designed for materials analysis! The relational database format of the PDF, coupled with the Java™ interface, promotes searches that can be permutated in any combination. PDF-4+ boasts nearly limitless search combinations using 48 different types of searches and 66 data fields. For Release 2007, four new searches were added and a statistical analysis package for x-y and histogram plots was incorporated. The combination of searches, plots and display fields are a powerful research tool.
In the examples above, one can see the wide range of I/Ic values for TiO2, and how these cluster with the polymorph type and systematically vary with cell volumes for rutile. This is an example where data mining along with graphical interpretation can lead the researcher to the appropriate references to use for quantitative analysis. The range in rutile cell volumes and I/Ic is attributed to wide variation in temperatures used in rutile synthesis. High quality room temperature mineral specimens of rutile exhibit a very narrow range of I/Ic of 3.52(2).
The plot demonstrates the histogram capability by plotting the number of primary references added to the PDF over a 20-year publication period. It also demonstrates the continuous input of new materials generated by global researchers into the PDF.
PDF-4+ provides users with comprehensive materials coverageand the power to data mine, identify and quantitate.
PDF-4 and PDF-2 Product Feature Comparison
PDF-4/MINERALS 2007 - Purchase
- 25,861 minerals entries
- ~4,300 mineral entries with atomic coordinates
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 25,861 unique entries.
The data are annually peer reviewed by a task group of mineralogists. This task group assigns mineral groups and super groups, classifications, and prototype structure types to assist users with identification and analysis. Approximately 4,300 mineral entries have been added from the Linus Pauling File and NIST. These entries include atomic coordinates, pattern simulations and molecular graphics as described in thePDF-4+ product description.
PDF-4/ORGANICS 2008 - Purchase
Designed for rapid materials identification with 341,540 entries!
New for 2008
- 2,000 new experimental entries
- ~27,000 new calculated entries
- 3,577 pharmaceutical entries
- 1,623 excipient entries
- 580 new entries with assigned functional groups
- 700 newly flagged 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 thousands 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/Ic 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 thousands 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.