Plotting DMFit data

SpinPlots provides functionality to easily plot fits of NMR data done using DMFit. Both 1D and 2D spectra are supported, including overlays, stacked views, and grid layouts.

Plotting 1D fits

To use Spinplots functions, you first need to export your 1D DMFit data, as follows:

1. Navigate to the menu: Decomposition → Export spec, model with all lines → Export as Ascii File.
2. Important: Ensure the file extension is either .hz (for data in Hz) or .ppm (for data in ppm).

The example below used data exported from a DMFit example showing a ³¹P NMR spectrum showing overlapping peaks.

import warnings
warnings.filterwarnings("ignore", category=UserWarning)
from spinplots.io import read_nmr

dmfit_data = read_nmr("../../data/DMFit/overlapping_spe_fit.ppm",
                      provider="dmfit")
dmfit_data.plot(xlim=(120, -70))

dmfit_data.plot(
    xlim=(120, -70),
    xaxislabel="$^{31}$P (ppm)",    # Add a label to the x-axis
    linewidth=2,                    # Increase width of spectrum
    model_linewidth=3,              # Increase width of model
    model_linestyle='-.',           # Change the linestyle of the model
    model_color='orange',           # Change the color of the model
    model_alpha=0.8,                # Transparency of the model
    deconv_show=False,              # Hide the deconvolution curves
    labels=["Spectrum", "Model"],   # Add a legend
)

Overlaying multiple 1D DMFit spectra

Multiple DMFit exports can be loaded and plotted together. Each spectrum is shown with its own color:

# Load the same file twice for demonstration (use different exports in practice)
multi_dmfit = read_nmr(
    ["../../data/DMFit/overlapping_spe_fit.ppm", "../../data/DMFit/overlapping_spe_fit.ppm"],
    provider="dmfit",
    tags=["Sample A", "Sample B"],
)
multi_dmfit.plot(
    color=["blue", "green"],
    xlim=(120, -70),
    labels=["Sample A", "Sample B"],
)

Stacked 1D DMFit spectra

Use stacked=True to offset spectra vertically, which is useful for comparing lineshapes:

multi_dmfit.plot(
    color=["blue", "green"],
    xlim=(120, -70),
    stacked=True,
    labels=["Sample A", "Sample B"],
)

Grid layout for 1D DMFit spectra

Use grid="1x2" to place each spectrum in its own subplot. Each subplot shows the experimental spectrum, the model fit, and the deconvoluted components:

multi_dmfit.plot(
    grid="1x2",
    color=["blue", "green"],
    xlim=(120, -70),
)

Plotting 2D fits

DMFit also allows fitting of 2D NMR spectra such as this ¹H-³¹P HETCOR example. To use such data in SpinPlots, you need to export the 2D spectrum and the model fit in DMFit as .ppm files.

# Read a 2D 1H-31P HETCOR spectrum and fit
hetcor = read_nmr(
    ['../../data/DMFit/hetcor_spectrum.ppm', 
     '../../data/DMFit/hetcor_model.ppm'],
    provider="dmfit",
    tags=["spectrum", "fit"],   
)

hetcor.plot(
    contour_start=10,
    contour_num=25,
    contour_factor=1.5,
    color=['black', 'red'],
    xlim=(38, 24),
    ylim=(22, 16),
    xaxislabel=r"$^{31}$P $\delta$ / ppm",
    yaxislabel=r"$^{1}$H $\delta$ / ppm",
)

Grid layout for 2D DMFit spectra

For 2D DMFit grid plots, data must be provided in pairs (experimental + model). Use grid="1x1" to show a single pair in a subplot with projections. Additional customization options include linewidth_contour, linewidth_proj, and diagonal:

multi_2d = read_nmr(
    ['../../data/DMFit/hetcor_spectrum.ppm', 
     '../../data/DMFit/hetcor_model.ppm',
     '../../data/DMFit/hetcor_spectrum.ppm', 
     '../../data/DMFit/hetcor_model.ppm'],
    provider="dmfit",
    tags=["spectrum A", "fit A", "spectrum B", "fit B"],
)


multi_2d.plot(
    grid="1x2",
    contour_start=10,
    contour_num=15,
    contour_factor=1.5,
    color=[["black", "red"], ["black", "green"]],
    xlim=(38, 24),
    ylim=(22, 16),
    linewidth_contour=0.8,
    linewidth_proj=1.2,
    xaxislabel=r"$^{31}$P $\delta$ / ppm",
    yaxislabel=r"$^{1}$H $\delta$ / ppm",
    titles=["Sample A", "Sample B"],
)