Spin System Simulator

Program from: Eugenio Alvarado

Short description (taken from Peter Lundberg)
Graphical NMR spin system simulation program, or SSS for short, for PC (Windows). Shows a tool for executing pulses (any phase), and delays, the complex density matrix in graphical form, the macroscopic vectors, and the populations. Homo- or heteronuclear experiments or a single spin simulation.

Short description - more emotional
The ideal tool to introduce - and understand - both the vector model and the density matrix approach. You can try to evaluate nearly all fundamental problems:

  • chemical shift evolution
  • effect of refocussing pulses
  • the BIRD (or TANGO) sequence
  • the INEPT principle
  • composite pulses
  • ...
Download locations
To our knowledge there is only one web location: Usage for educational purposes
There is a nice page written by Scott van Bramer available.

Final remarks
This is an old program. I believe this excellent program should be maintained for the future. I have asked the original author and got the following kind answers:

  • The program still works under Windows 98. I wish I could recompile it or make improvements. Unfortunately, I wrote the program in a now defunct language called Actor. That was an object-oriented language specifically for Windows that made programming easier (at least in theory). I chose the language because I wanted to learn object-oriented programming. At any rate, I do not have the Actor compiler any more. I think the language is similar to C++, or at least it should be easier to port to C++ than to other languages like C. But I don't have a recent C, C++ or other compiler available. So, due to this and my present responsabilities I am unable to maintain it. But I can send you the source code if you wish.
    I am very happy that you find my program useful. Please use it as you see fit and share it with others. The program is most useful for understanding pulse sequences where the classical vector model is not appropriate, like INEPT, INADEQUATE, BIRD and other filters, and to design pulse and phase sequences. If you enter the INEPT sequence you will see the transfer of population, and you can see the difference with different nuclei. It is all a matter of entering pulse sequences (including the phases) and see the result in the magnetization.
    I hope you like it and use it. Let me know if you want the source.


What do you think? Is there anyone who could maintain this really useful program?