September 2024

Pyromorphite:PDF Entry 00-074-0931

Use your mouse to hover over the interactive elements within the red boxes on the PDF entry and click to learn more.

EBSD Pattern EBSD patterns are electron diffraction simulations based on algorithms originally developed by R.P. Goehner and J.R. Michael [1]. These patterns are useful in confirming phase identity, crystallite orientation, and crystalline symmetry. The Kikuchi line positions are determined kinematically using unit cell parameters and space group extinction conditions associated with the PDF entry.

EBSD Extension • Designed to plot K-patterns (Kikuchi & Kossel patterns) • Toggle between gnomonic projection and stereographic projection • For Kossel patterns, up to three Kα1-wavelengths of elements in the chemical formula are used

3D structureThe 3D Structure shows the three-dimensional representations of molecular structures. Click the play button to see the structure in 360 degrees.

Simulated Profile The Simulated Profile shows the one-dimensional representation of powder diffraction patterns using an interactive graph. This graph is displayed in multiple places throughout the program and the available settings can change due to the context of the current graph.

SAED Extension • Simulation of freely rotatable SAED patterns from Structures • Import images and apply image processing options • Synchronized Structure Display and Stereographic Projection • Searchable Reflection List with Absences • Measurement Tools: Scalebar, Ruler, Protractor, Indexing Grid • Measure Distances and Angles of clicked spots

SAED Pattern SAED patterns are electron diffraction simulations based on algorithms originally developed by R.P. Goehner and J.R. Michael [1]. These patterns are useful in confirming phase identity, crystallite orientation, and crystalline symmetry. The spots are determined kinematically using unit cell parameters and space group extinction conditions associated with the PDF entry.

Ring Pattern Ring patterns provides a two-dimensional (2D) simulation of the diffraction pattern for a given phase as it would appear on a flat 2D detector such as photographic film, phosphor image plates, or solid-state arrays. The simulation assumes uniaxial positioning of the detector (transmission geometry with incident beam centered) and an infinite number of randomly oriented crystallites.

Crystal: This tab displays general crystallographic data for the PDF entry as calculated by ICDD, such as the space group and unit cell.

References: This tab displays all of the bibliographic references used to publish the PDF entry.

Experimental: This tab displays the experimental conditions for the PDF entry, such as the radiation type and if an internal standard was used.

Raw Diffraction Data When applicable, this shows a plot of the PDF entry’s raw diffraction data (also known as PD3 patterns). These are typically nanocrystalline, semicrystalline, or amorphous materials.

Classifications: This tab displays the various classifications for the PDF entry, such as the subfiles and mineral/zeolite classifications.

PDF: This tab displays general information about the PDF entry, such as the various formulas and names.

BFDH ExtensionThis module for the BFDH crystal morphology prediction (Bravais-Friedel-Donnay-Harker) represents an extension app that is accessible in PDF-5+. While the original BFDH method for slow growth with D~1/d without structure considerations is the default, one can also choose methods for supersaturation / rapid growth with D~Exp(-kd), after E.Dowty. Furthermore one may promote the presence of faces by including their calculated structure factors Fc(hkl) as "XRD Multipliers", when structure data are available. The option for the Scherrer shape is experimental and is supposed to result in the average crystallite shape actually present in a profile-fitted powder sample.

Temperature Series If the current PDF entry is part of a temperature series, this button will list all of the PDF entries that are part of that temperature series. You can use the temperature series listing to plot thermal expansion coefficients and create other useful graphs.

Physical: This tab displays general crystallographic data for the PDF entry as defined by the author, such as the space group and unit cell.

Structure: This tab displays structural data for the PDF entry, such as the atomic coordinates and space group symmetry operators.

Toolbox The Toolbox allows you to dynamically calculate individual peaks and peak lists based on a user-defined wavelength, unit cell, and set of miller indices.

Cross-references: This tab displays the cross-references for the PDF entry, such as the alternate and related PDF entries.

Comments: This tab displays the ICDD editorial comments and user-generated comments for the PDF entry.

Bonds The Bonds show the asymmetric units’ interatomic bond lengths and angles for PDF entries with atomic coordinates. A histogram shows the number of neighboring atoms at interatomic lengths up to 10 Å.

Bonds Histogram Extension This tool presents bond distance histograms for selectable element pairs. The distances were calculated from the structure phases in the database. For each structure a minimum distance and the average distance was created for each present element pair within a range based on the radii sum of both elements. A pair of elements may be selected from a periodic table, an element matrix or from a search box. The tabulated distances are then listed and one can select individual entries for the structure display by selecting an entry from the list or by clicking in the histogram.