TOPAS-Academic - Version 9

by Coelho Software 2026 AlanCoelho@bigpond.com
Australian Business Number 70 827 688 789

Buy a licence · 400 Euros/year

Introduction

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.
  • Modulated 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.

Availability

TOPAS-Academic is 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.

Writing input

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 and TOPilot AI driven work.

Collaboration with John Evans and TOPAS Forum

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

TOPAS-Academic / TOPAS comparison

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 TOPAS offers the use of Windows dialogs.

Purchasing — Fixed Term licenses

Each license runs one instance of the program on a specific computer. More than one person can use that computer, but not at the same time; TA.EXE and TC.EXE can both be run at once. 10% VAT is charged for Australian customers only.
Buy a licence · 400 Euros/year

A purchase costs 400 Euros × the number of years × the number of licenses.

Online purchases only — invoices are not available.

If you are unsure about eligibility; send an e-mail address to AlanCoelho@bigpond.com.

Important information for purchasing TOPAS-Academic

  • All forms must be completed by the customer, not the supplier.
  • Delivery of the license is by e-mail to a university/lab e-mail address after payment has been made.
  • The licence belongs to the university and is for use by its students and staff.
  • The program operates only on 64 bit computers.

    • Licence Agreement

    Coelho Software, Brisbane, Australia. September 2026.

    1. Who may use it. Degree-granting institutions (universities, university-run institutes, laboratories and schools) and synchrotron and neutron research centres only.
    2. What a licence covers. One computer, one user at a time. The licence belongs to the institution, is for its staff and students, and may not be given, sold or sublicensed.
    3. Moving a licence. A licence may be moved at no charge to another computer in the same department, if the Software is removed from the old one.
    4. Ownership. The Software remains ours and is copyright. You may not reverse engineer it or defeat its licensing, except where the law permits.
    5. Term. A licence runs for the years paid for, from delivery of the licence file or 12 months after payment, whichever is earlier, and then stops unless renewed.
    6. Updates. Updates released during the term are included.
    7. Internet. The computer must connect to the internet at least every three months to confirm the licence, or the Software stops until it does.
    8. Ending the agreement. We may end the licence if you breach this agreement; you must then erase every copy.
    9. Warranty. For 90 days from purchase, the Software will execute its programming instructions when properly installed. No other warranty is given, including that it will run without interruption or error.
    10. Liability. We are not liable for any direct or indirect damage from using the Software or from lack of support. Rights under the Australian Consumer Law that cannot be excluded are unaffected; where liability can be limited, it is limited to replacing the Software or refunding the fee.
    11. Data. At startup and when a refinement runs, the Software contacts our server for licence and update checks; the server logs the IP address, time and licence number, and the logs expire automatically. No user data, structures, results, file names or settings are sent. The ta.dxx file used to create a licence holds hardware identifiers, the Windows user name and the install folder, and is kept while the licence is supported. Nothing is sold, shared or used for advertising.
    12. Law. Queensland law applies, unless your institution is barred by law from agreeing to this. Disputes may be heard in the Queensland courts, though not only there.

    Acknowledgements

    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.

    Downloads

    Skeletons

    Helper programs

    Please do not download

    For reading brml files