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 PDF-4+ 2021

Phase Identification & Quantitation

PDF-4+ 2021 contains 444,100+ entries. It combines the world’s largest sources of inorganic diffraction data from crystals and powders into a single database. The result is a comprehensive collection of inorganic materials, produced in a standardized format that can be rapidly searched for unknown phase identification. Extensive data mining is facilitated with 131 display fields coupled with 77 searches.

PDF-4+ is designed to support automated quantitative analyses by providing key reference data required for these analyses. It also contains an array of tools that supplement conventional analyses, such as a full suite of data simulation programs enabling the analysis of neutron, electron, and synchrotron data, in addition to conventional X-ray data.

PDF-4+ features digitized patterns, molecular graphics, and atomic coordinates. These features incorporated into PDF-4+ enhance the ability to do quantitative analysis using third party software by any of three methods: Rietveld Analysis, Reference Intensity Ratio (RIR) Method, or Total Pattern Analysis.

The Powder Diffraction FileTM (PDF®)  
Not sure which database you should purchase? Search using chemical name, formula, and elements
to find out which ICDD database product is right for you.
Products related to PDF-4+ 2021:
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Using PDF-4+ 2021

Key Points

  • Rapid phase identification designed to support automated quantitative analyses
  • Features 444,100+ entries, including 336,500+ entries with atomic coordinates
  • 47,100+ entries for organic materials
  • Integrated data mining software
  • All entries have digital patterns for use in total pattern analysis
  • More than 343,400+ entries have I/Ic values for quantitative analysis by Reference Intensity Ratio
  • Combines powder and single crystal data
  • Includes crystalline, semi-crystalline and amorphous solid
    state materials
  • World’s largest and most diverse collection of structures for
    inorganic materials
  • Extensive data mining is facilitated with 131 display fields
    coupled with 77 searches
  • One (1) year license serviced by subscription


  • Number of entries – 444,100+
  • New entries  – 17,944


  • Entries with Simulated Digital Patterns – 444,100+
  • Entries with Reference Intensity Ratio (I/Ic) – 343,400+
  • Entries with Atomic Coordinates – 336,580+
  • Entries with Experimental Raw Data Digital Patterns – 15,700+


  • 77 types of Search Selections
  • 131 types of Display Fields

database sources

Our collaborative partners include:
  • ICDD Powders (00) – International Centre for Diffraction Data Newtown Square, PA, USA
  • ICSD (01) – Fachinformationszentrum Karlsruhe (FIZ) Karlsruhe, Germany-Inorganic Crystal Structure Database
  • NIST (03) – National Institute of Standards and Technology, Gaithersburg, Maryland, USA
  • MPDS (04) – Material Phases Data System, Vitznau, Switzerland-Linus Pauling File (LPF)
  • ICDD Single Crystal Data (05) – International Centre for Diffraction Data Newtown Square, PA, USA


Four select subfiles out of 30:
  • Metal & Alloys – 162,136
  • Mineral & Related Materials – 48,946
  • Ceramics – 19,583
  • Common Phases –  22,670

All subfiles: Alkaloid , Amino Acid, Peptide & Complex, Battery Material, Bioactive, Carbohydrate, Cement & Hydration Product, Ceramic, Common Phase, Education, Explosive, Forensic, Hydrogen Storage Material, Inorganic, Intercalate, Ionic Conductor, Merck, Metal & Alloy, Micro & Mesoporous, Mineral Related, Modulated Structure, NBS, Nucleoside & Nucleotide, Organic, Pharmaceutical, Pigment & Dye, Polymer, Porphyrin, Corrin & Complex, Steroid, Superconducting Material, Terpene, Thermoelectric Material

  • PDF-4+ Entries
  • Atomic Coordinates
Search Subfiles
  • Subfile – select filters related to assigned subfiles/subclass.
  • Environment – select filters related to the environment (especially temperature and pressure).
  • Atomic Coordinates – filters based on entries that contain atomic coordinates or a cross-reference to an entry with atomic coordinates.
  • Raw Diffraction Data (PD3) – filters based on entries with high quality raw experimental data that can consist of nano-crystalline materials, semi-crystalline materials, or amorphous materials.
  • Status – select filters based on the status of the pattern, which can be Primary, Alternate, or Deleted.
  • Quality Mark (QM) – select filters related to the quality evaluation assigned to the data.
  • Database – search the entire database or select the data entry source (i.e., ICDD (00) – ICDD’s experimental patterns).

A Powder Diffraction FileTM (PDF) Card displays all of the scientific and bibliographic data available for a particular PDF entry and is organized into the following categories:

Temperature Series, Toolbox, Property Sheet, 2D Structure, View 3D Structure, Bond Distances/Angles, Simulated Electron Spot Pattern, Electron Backscattering Pattern, Ring Pattern, Simulated Diffraction Profile, Raw Diffraction Data (PD3)*.

  • Equipment factors
  • Historic stick pattern and simulated pattern
  • Tabular view of reported data: PDF, Experimental, Physical, Crystal, Optical, Structure, Classifications, Cross-references, References, Comments

*Note: The availability of each feature varies by PDF entry.

ICDD’s search indexing program, SIeve+ for PDF-4+, is designed to search and identify unknown materials. SIeve+ is integrated into the ICDD databases to allow the use of the extensive data mining interfaces, searches, and sorts available to improve accuracy and precision of the identification process. For example, users can utilize the extensive permutable searches in each database, then define their own search subfile or use any of the “application or expert-defined” subfiles and subclasses to increase the accuracy of their phase identification. In many cases, this provides a unique capability to analyze the most difficult problems.

SIeve+ offers a variety of algorithms and options that allow users to optimize results for particular chemistries and both standard and non-standard diffraction systems. SIeve+ features automatic rotation of the eight strongest lines (Hanawalt) or the eight longest of the strongest lines (Fink) or the eight longest lines (Long8) to look for entries that exhibit the best Goodness of Match (GOM). In the last few years, new algorithms have been added to identify non-crystalline materials and complex multi-phase specimens. Most of the algorithms were developed and optimized for a particular type of analysis and the options provide the user with a wide breadth of analytical capability. SIeve+ can be complementary with most commercial software programs. This complementary nature demonstrates the strength of SIeve+ in the analysis of minor and trace phases where the full filtering capability of the PDF-4 databases can be applied.

Want to learn more about SIeve+? Click here.

Try SIeve+ for a free 30-day trial after you install your database and discover its phase identification capability. At the end of the 30-day trial period, contact ICDD or your vendor for a license. Please note: ICDD’s search-indexing software is included in PDF-2 (SIeve) and PDF-4/Organics (SIeve+) free of charge.]

key points
  • 30 day trial for FREE
  • Match filter algorithms – better results, more accuracy
  • Import d-I list, 1D diffraction patterns and 2d diffraction patterns
  • Displays simulated diffraction patterns for phases in graph
  • Qualitative and quantitative analysis
  • Directly interfaces to all PDF databases for accurate filtering and analysis – full data mining
  • Excels at the identification of low concentration phases
  • Supports X-ray, synchrotron, electron, and
    neutron data
  • “Intelligent” RIR for semiquantitative analysis.

Scientists using PDF-4/Axiom

purchase pdf-4+

  • Intel® Core™ 2 Duo processor or better
  • Supported Microsoft® Operating Systems:
    • Windows® 7 SP1
    • Windows® 8
    • Windows® 8.1
    • Windows® 10
  • NTFS File System required
  • 4 GB of System Memory
  • Installation requires 10 GB of hard-disk space

Note: It is necessary to have Administrator privileges or use the Administrator account and password for your local domain in order to install this product. You can obtain your domain by running the following command line in a Command Prompt window: ipconfig/all. Your local domain will appear next to the “Host” label.

Prior Release Requirements

2020 Release

2020 Products PDF-4+ 2020
Intel® Core™ 2 Duo  processor or better X
Supported Microsoft® Operating Systems:
   Windows Vista® (32-bit) SP2 X
   Windows® 7 (32 & 64-bit) SP1 X
   Windows® 8 (32 & 64-bit) X
   Windows® 8.1 (32 & 64-bit) X
   Windows® 10 X
NTFS file system required X
System memory recommended 4 GB
Hard-disk space required 10 GB

2019 Release

2019 Products PDF-4+ 2019
Intel® Core™ 2 Duo  processor or better X
Supported Microsoft® Operating Systems:
   Windows Vista® (32-bit) SP2 X
   Windows® 7 (32 & 64-bit) SP1 X
   Windows® 8 (32 & 64-bit) X
   Windows® 8.1 (32 & 64-bit) X
   Windows® 10 X
NTFS file system required X
System memory recommended 4 GB
Hard-disk space required 10 GB

2018 Release

2018 Products PDF-4+ 2018
Intel® Core™ 2 Duo  processor or better X
Supported Microsoft® Operating Systems:
   Windows Vista® (32-bit) SP2 X
   Windows® 7 (32 & 64-bit) SP1 X
   Windows® 8 (32 & 64-bit) X
   Windows® 8.1 (32 & 64-bit) X
   Windows® 10 X
NTFS file system required X
System memory recommended 4 GB
Hard-disk space required 10 GB

2016 Release

2016 Products PDF-4+ 2016
Intel® Core™ 2 Duo  processor or better X
Supported Microsoft® Operating Systems:
   Windows Vista® (32-bit) SP2 X
   Windows® 7 (32 & 64-bit) SP1 X
   Windows® 8 (32 & 64-bit) X
   Windows® 8.1 (32 & 64-bit) X
   Windows® 10 X
NTFS file system required X
System memory recommended 4 GB
Hard-disk space required 9 GB

This product is serviced by subscription only and requires registration. Your automatic renewal for this product is based on the original invoice date. If you cannot take advantage of the automatic subscription contact sales@icdd.com.

The term of the license shall be one (1) year from the license registration key date. Registration is required upon installation. A registration key will be issued within 48 hours (Monday through Friday) of receipt of your information.

The PDF-4+ 2021 database contains integrated data mining software and ICDD’s search-indexing software, SIeve+ (sold separately). SIeve+ activates for a free 30-day trial period upon installation. In order for SIeve+ to be activated past the 30 days, a license for SIeve+ must be purchased from ICDD or your vendor.

Explore the capabilities of PDF-4+ 2021 with our extensive Help documentation, online tutorials, and videos. The Help files include a Table of Contents and fundamental information on how to use the database. The online tutorials are designed to demonstrate the features, applications, hints and shortcuts for your PDF-4+ product.

How to properly install your PDF product

Media Available for Purchase –

Vendor Software –
ICDD partners with licensed software developers, including equipment manufacturers and independent developers to develop commercial data analysis programs that work seamlessly with our databases.

Ordering Information –
Please send us a sales order via fax, email or mail. ICDD requires the name of the end user on all orders. Use product codes in your order, if possible. A convenient Order/Quotation Form can be found here.

Pricing – 
The prices listed herein supersede all others previously published and are subject to change without notice. ICDD reserves the right to discontinue any product at its discretion. See the Price List or contactour Customer Service Department for the most recent product information and pricing.

Return Policy – 
Products may be returned within 30 days from the invoice date for a full refund or credit (excluding shipping/handling). Products must be returned in original condition to qualify for a refund or credit. Registered products do not qualify. Please complete a Return Merchandise Authorization (RMA) form to receive approval prior to returning product. Defective products will be replaced promptly, but must be returned for testing.

Warranty Policy –
Customers’ sole remedy for any defective Licensed Product shall be replacement of the Licensed Product, which right must be exercised by written notice given within 30 days of purchase. Defective products will be replaced promptly, but must be returned for testing.

Payment Terms –
Wire transfers, credit cards (MasterCard, Visa, American Express) and checks in USD$ and drawn on U.S. banks are acceptable forms of payment. Letters of credit will not be accepted. Payment is due within 30 days from invoice date. Finance charges of 1.5% per month (annual percentage rate of 18%) may be applied to overdue balances.

Licensing –
ICDD licenses the use of the Powder Diffraction File and software. Licensing for the PDF-2, PDF-4 product line, and associated software (SIeve and SIeve+) are packaged with the DVD, USB, and/or dongle. ICDD’s product licenses are nontransferable and intended for use on a single computer. It is expressly prohibited to access the database over a network or access the database using desktop sharing or screen sharing software*. Please refer to the sales descriptions and product policies for further information on licensing.
*Contact ICDD for WebPDF-4+ licensing.

Site Licensing
Multi-year Licensing

Shipment –
All orders shipped by ICDD are F.O.B. Newtown Square, PA, U.S.A. Import duties and all taxes are not included in pricing and are the sole responsibility of the customer. Shipment will be made by a commercial carrier chosen by ICDD. For your convenience, shipping charges will be added to all invoices. Shipments can be insured upon request; additional charges will apply.

Orders & Delivery –
All orders are handled on a First In, First Out (FIFO) priority queue. Delivery will occur approximately 30 days on items in stock after receipt of completed order.

Note: Customers in Japan, South Korea and Russia must order through an ICDD licensed vendor.

Still need help?

Call (610) 325-9814 or toll free (866) 378-9331 (U.S and Canada only) or email sales@icdd.com

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