SpinSpec

Hamiltonian-based NMR spectrum modeling

Examples

Title

Gyromagnetic ratios (MHz/T)

Isotope γ values

Chemical shifts (ppm)

External field enter as ¹H frequency (MHz)

Default: magnetic field in mT

J-couplings

Displayed spin numbers

Graph heights

line width and spectrum width (Hz)

Open set

Form is ready.

A web interface for preparing .set files, exploring examples, and running NMR spectrum calculations.

Online NMR Spectrum Simulation

SpinSpec is an online NMR spectrum simulator for interactive visualization of J-coupled spin systems. The platform is based on exact spin Hamiltonian diagonalization and allows exploration of spectra under different magnetic field conditions.

Features

• High-resolution J-coupled spectrum simulation
• Arbitrary magnetic field values from high-field to low-field regimes
• Interactive visualization of spin groups
• Ready-to-use molecular examples
• Support for custom spin systems and .set files

Quick start

Choose one of the prepared examples or enter your own spin-system parameters: gyromagnetic ratios, chemical shifts, J-coupling constants, and magnetic field. Spin numbering starts from zero.

Tutorial page, Tutorial videos and example datasets are available to help new users quickly understand the interface and reproduce experimental spectra.

Model validation

The current implementation reproduces experimental high-field spectra well and shows qualitatively correct spectral evolution toward Earth-field conditions. Zero-field spectra may require additional validation and density-matrix-based treatment of transition amplitudes.

The project is developed with participation of researchers affiliated with Gebze Technical University (Turkey) and Saint Petersburg State University (Russia).

Feedback and suggestions are welcome. Please cite the source if you use the results.