TOPAS-Academic Version 8

TOPAS-Academic is a general non-linear least squares system driven by a scripting language. At its core is a bound-constrained minimization engine wrapped in a computer algebra system. Subject-specific modules, such as Rietveld refinement, are built on that foundation, which is why parameters, constraints and restraints, written as ordinary equations, can be applied across any of them, and across many data sets at once.

It is used for:

• Rietveld, Pawley and Le Bail refinement of laboratory X-ray, synchrotron and neutron data, including time-of-flight.
• Single crystal refinement, including twinning.
• Structure solution in real space by simulated annealing, and from powder data by charge flipping.
• Indexing.
• Pair distribution function and total scattering analysis.
• Stacking faults and layered disorder.
• Quantitative phase analysis.
• Magnetic structures.
• Energy minimization and molecular dynamics.
• Parametric, in situ and operando studies across thousands of data sets.

Published work using TOPAS spans battery and energy storage materials, catalysis, metal-organic frameworks and zeolites, cements and minerals, alloys and metallurgy, perovskites and photovoltaics, pharmaceutical polymorphs, thermoelectrics, phosphors, fuel cells and ionic conductors, and functional ceramics.

Version 8 of TOPAS-Academic is now available to:

1. Degree-granting institutions comprising universities, university run institutes, laboratories and schools.
2. Synchrotron and neutron research centers.

TOPAS-Academic comprises all the functionality of BRUKER-AXS TOPAS operating in Launch mode including all graphics and OpenGL structure editor and viewer. Launch mode is where the full functionality of TOPAS is realized.

Input is via an INP script; with a good editor and a help system, writing INP scripts is straightforward. To bring standardization to editing INP files, John Evans has built a complete working environment on top of the open source editor VS Code here.

A command line program, TC.EXE, comprises the kernel of TA and is used for batch processing.

John Evans' involvement in TOPAS-Academic continues; his many ideas, suggestions, tutorials and rigorous testing has led to a multitude of breakthroughs and improvements.

• John Evans TOPAS-Academic Page
• Tutorials including starting tutorials
• TOPAS Forum

There are no differences between the kernel of TA and Bruker-AXS TOPAS for the same version number. TA will always comprise the latest kernel.

There are no differences in regard to single crystal refinement, structure solution, neutron TOF and non-standard Rietveld refinement. See starting tutorials here.

There are some differences in how data input is handled for peak fitting and indexing, see here.

For standard Rietveld refinement then TOPAS offers the use of Windows dialogs.

• All forms must be completed by the customer, not the supplier.
• Use of TOPAS-Academic requires basic computer literacy.
• Payment is by bank transfer or credit card.
• Delivery of software is by e-mail to a university/lab e-mail address after payment has been made.
• The payment confirmation email serves as the receipt.
• Invoices are issued once; customers may add their own order numbers to the PDF.
• Invoice dates are not altered.
• The licence belongs to the university and is for use by its students and staff.
• The program operates only on 64 bit computers.

Each license will run one instance of the program on a specific computer. More than one person can of course use that computer but not at the same time; TA.EXE and TC.EXE can be both run at the same time. 10% VAT is charged for Australian customers only.

From a valid university e-mail address, send an e-mail to AlanCoelho@bigpond.com. PhD students should supply their supervisor or department's head web and e-mail address. Additional suggestions for verifying your academic status are considered.

Support regarding suggested techniques and program operation is generously given via e-mail. However the wholesale solving of problems requiring sometimes days of work is not support; it is consulting.

The Software checks for updates on startup and records standard access information (IP address, date/time, hardware derived code). A similar request occurs once per startup when a refinement is run to identify active installations. No user data, structures, results, filenames, or settings are transmitted. Logs remain on the server and expire automatically. Licence creation requires a .dxx file containing hardware identifiers; this is retained while the licence is supported. Information is used solely for licence enforcement and is not sold, shared, or used for advertising.

BRUKER-AXS and in particular Dr. Arnt Kern for recognising the needs of the scientific community and granting permanent use of TOPAS code in TOPAS-Academic.

John Evans for continuous support, testing and guidance in the development of TA's functionality.