Tabular processor for X-ray diffractometry

Introduction

The program RTP can be used by the specialists in the area of X-ray analysis of crystal materials in various directions of science and technology. It calculates the crystal lattice parameters (lattice constants) for syngonies from cubic to triclinic and also calculates the theoretical angles of diffraction by known parameters and indices. Program is able to determine the displacement of the reflecting area from the goniometer plane by minimum of divergence and calculate the corresponding correction. Calculation of theoretical density and attenuation length by chemical formula and cell volume allows to calculate parameters more precisely. In addition, program allows to perform the indexing by shuffle and by known indices.

Technical characteristics

• Calculated lattice types: from cubic to triclinic.
• Calculated data: lattice constants and cell volume; c/a relation for hexagonal, tetragonal and orthorhombic lattice; orthorhombic splitting.
• Limits by indices h k l: from 0 to 99
• Limits by interplanar distances: 0.02...99 Å
• Limits by lattice edges a, b, c: 2...99 Å
• Maximum line number in the table: 440
• Precision of calculated parameters: 0.0001 (0.00001) Å
• Labelling the set of lines in the table as a separate phase (up to 4 phases).
• Calculation of the angle position of lines 2θ with generation of h k l by given parameters and lattice type.
• Calculation of the angle position of lines 2θ by given parameters and indices h k l listed in the table.
• Calculation of the specimen displacement by experimental angles of standard substance or by minimal divergence of calculated results.
• Calculation of the molar mass M, theoretical density ρ and attenuation length 1/μ by the chemical formula and cell volume.
• Indexing with shuffle or by known h k l methods for lattices from cubic up to monoclinic.
• Reading the PDF cards in *.aid format saved by PCPDFWIN program (PDF-2 software kit); reading the text files with 2θ or d, intensity and indices (for example, exported from a spreadsheet); reading the American Mineralogist Crystal Structure Database (AMS) data files.
• Saving 2θ and intensity table in the text format for a phase analysis program and the table with results in CSV format for a spreadsheet.
• Data exchange with another RTP session or external programs using Windows clipboard (since version 5.0).

System requirements

Win32 version: Windows XP or later, mouse
(Windows 7 or later is highly recommended).
Font for printing: Lucida Console 14 pt.
Internet connection, only for version update.

Help and documentation

Examples of calculations

Downloads

Main archive rtp32.cab contains all components of the program (RTP32.EXE, RTP.CHM, RTPWL.INI, RTPAM.INI). In addition, it includes the history file with the list of recent changes. Current program version is 5.0, it has the reworked user interface and full support of clipboard operations. You can also download the previous version 4.8 which was tested much longer, but does not have the recent improvements.

Another archive includes the test examples, which contain the tables of diffraction lines of various samples or the data taken from PDF for calculation the parameters; examples are especially useful to understand the indexing process. Remark: this set of examples is outdated, more contemporary version is in work.

All files are free of malware or advertising, they do not contain hidden functions or external links, besides the home page and section "References" in documentation. Automatic check for update is switched off by default, so the program never uses the Internet connection without your approval. You can perform additional security check using the VirusTotal scan by the reference to rtp32.cab or check the whole domain slavic.me.

Remark: you can unpack the cab archives using the Explorer or the program extrac32.exe.

Screens

Screen of the program RTP 4.8 (December 2023) in Windows 11.
Results of calculation of silicon oxide lattice (PDF-2 card 46-1045). Font Lucida Console 14 pt, classic colour scheme.

Screen of the program RTP 5.0 beta (April 2024). Font Cambria 14 pt, light scheme.

a)

b)

c)

Correction of displacement of MoU₂ specimen (PDF-2 card 12-0296).

a) Details of calculation of original card. On the top is the stripe chart of distribution of deviations of experimental angles 2θ from the theoretical angles calculated by lattice parameters. Axis X is the deviation in degree, axis Y — intensity in logarithmic scale. Colour areas show the intervals of experimental precision (0.15 degree in this case), multipliers are on the top of chart. Vertical dashed line shows the mean deviation, which is significantly shifted from zero. Details are below the chart.

b) Graph of dependence of the root mean square deviation by 2θ in degree on simulated specimen displacement in millimetres. Minimum of dependence shows the displacement of specimen in goniometer.

c) Details of calculation after applying of correction by displacement.

Also RTP can calculate the atomic composition of some sentences.