Documentation on Read the Docs
nmrmint is an application for creating simulated complete NMR spectra (currently 1H NMR only) for use in chemical education. The application will 'mint' an NMR spectrum from user-provided chemical shifts and coupling constants.
I strongly believe that using actual experimental data for classes and exams is to be preferred. However, sometimes it can be hard to find spectra of sufficient quality for printing on exams. You may have a spectrum that would be easily solved at higher field strength, but you can only find spectra taken in lower fields where second-order effects make analysis more difficult. Or, conversely, you may have a high-quality spectrum that you want simulated at lower field strengh in order to demonstrate second-order features such as AB quartets, ABX systems, or AA'XX' (e.g. para-substituted benzenes). In such cases, nmrmint will provide you with that spectrum you need for tomorrow's quiz.
For each subspectrum simulation, the user can choose either first-order simulation for individual chemical shift-equivalent nuclei (doublets, triplets, doublet-of-doublets, etc.), or a second-order simulation of a two- to eight-nuclei spin system.
Version 0.3 (beta) features a completely reworked, more user-friendly GUI than v0.2 (alpha). The following features have been added:
- Individual subspectra can be created, added, deleted, and cycled through
- Individual subspectra can be toggled between being added to the total spectrum, and not being added.
- Each subspectrum can have its own linewidth (peak width at half height) set, allowing simulation of broadened signals such as OH/NH protons.
- The frequency of the spectrometer (i.e. frequency in MHz that TMS protons resonate at) can be changed at will, updating the entire spectrum.
- The minimum/maximum ppm limits for the total spectrum can be changed. Currently the limit is hardcoded from -1 to +15 ppm.
Desirable features, and known issues, include:
- Second-order simulation of > 8 nuclei. Currently, the calculations slow down dramatically with > 8 nuclei. Future code optimizations may allow this to be expanded. There may also be simplifications possible for larger systems, such as alkyl chains attached to a carbon with diastereotopic protons.
- Creating expansions. The current workaround is to use the min/max ppm entries and individually save these "zoom-ins" of the total spectrum. The built-in matplotlib toolbar allows for expanding regions of the spectrum, but the built-in "save" (floppy disk icon) saves both top and bottom spectra as a .png file that would require editing.
- simulating other spectra, such as carbon-13.
and in the longer term:
- integration
- peak picking
- expansions
Stand-alone, one-file executable apps for Mac OSX and Windows 64-bit can be found under releases. .. _releases: https://github.com/sametz/nmrmint/releases/tag/v0.3.2-beta
The project is beta and subject to change. The master branch should maintain the latest functional program. If you're curious, and have a Python 3 installation (v3.6 was used for development), you can download the project folders, install the requirements in requirements.txt if necessary, and run main.py from the command line.
See CHANGELOG.rst for the map towards a version 1.0.
The author is neither a professional programmer nor a professional NMR spectroscopist. I welcome feedback on this project. Feel free to leave an issue on Github, or contact me by email (mylastname at udel dot edu).
This project is inspired by Hans Reich's WINDNMR application. nmrmint initializes its simulations with the same variables as WINDNMR's defaults, to verify that the simulation is performing correctly.