Predict & Compare

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(NMR plugin is needed)
 
This feature will display in stacked mode, the experimental dataset and a simulation of the spectrum of the molecular structure present in the spectral window, highlighting the expected chemical shifts when the user hovers the mouse over a proton or a carbon. This tool can be used of assistance in the process of assigning 1H and 13C NMR spectra.

 

The user will be able to use this tool with 1H and 13C NMR spectra just by pasting the applicable molecular structure (quinine, in this example) over the spectrum and following the menu 'Prediction/Predict & Compare'. The same feature can be applied by selecting the molecule from the Compounds Table (without a need for having the molecule pasted on the relevant page, affording users the flexibility to run different predictions without having to generate many instances of the molecule on their report).

 

After the prediction is run, Mnova synthesizes the corresponding 1H-NMR spectrum using a rigorous full quantum mechanics method taking into account any second order effect present in the predicted spin(s) systems(s).

For example, in the figure below, you can see the results of running a prediction and comparing the resulting 1H spectrum with its experimental counterpart:

 

Predict and Compare1

 

As you can see, you will get the predicted spectrum on top with the proton assignments labels. You can draw (or load) a second molecule over the 'Predict&Compare' result, in order to get a new prediction in the stack:
 
predictCompare2

 

Hovering the mouse over the assignment labels and clicking&dragging will change the chemical shift in in real time:

 

predictANDCompare

 

Even you can graphically modified the predited coupling constants (just by clicking&dragging) if you have selected the option to show the coupling tree in the Multiplet properties

 

Jmove

Once you have modified the prediction, you can update those changes to the prediction Database to enhance the prediction results of similar structures. To do it, just right click on the molecular structure and select 'Update Prediction DB':

prediction DB

 

If you load a 1H-NMR spectrum with a multiplet analysis and run Predict and Compare; you will get a stack plot with the multiplet boxes displayed in the experimental spectrum, so you can easily assign those multiplets to the molecular structure and finally update the 'Prediction DB' if you wish:

predictandCompare_multiplets