jsNMR help

jsNMR is a lightweight self-contained NMR spectrum viewer and data exporting program for 1D NMR data. It consists of a single HTML file with JavaScript functionality to achieve this. There is a number of functions as explained below.

Loading a spectrum

To load a spectrum you have three options

Zoom and pan

Horizontal and vertical zooming is performed by activating the relevant buttons and use the mouse (computer) or zoom and pinch gestures (mobile device). You may always return to the full spectrum view by invoking the full button.

Processing and analysis

You have the possibility to make simple postprocessing like phasing the spectrum.
On a computer, use the left mouse button and drag up or down to phase the spectrum with a zero-order phase shift. If first-order phase shift is required, the position where you did the zero-order phase shift is stored as the pivot point. Then move the cursor to another peak, press the Alt-key and move the mouse up or down to invoke a first-order phase shift.
On a portable device, you use one finger to do a zero-order phase shift, then use two fingers to do a first-order phase shift. The position of your first finger press is the pivot point.
Peak picking is done by selecting the peak-picking button and use the mouse to select a peak. Click with the mouse over the peak you want to measure. If you are slightly off, it doesn't matter. jsNMR will select the most nearby peak for you.
Integration of peaks is done using the mouse. Press the mouse on one side of the peak and drag the mouse to the other side. The selected region will be integrated, and the result will be displayed (in arbitrary units with the weakest peak integrated to 1).
Working a large dataset in JavaScript may lead to long response times when the mouse is pressed etc. Use the compress dataset button to provide a copy of the dataset with half the number of data points. To avoid truncation wiggles, jsNMR provides a dataset where a slight linebroadening is applied, and therefore the intensities of the different peaks may not be exactly the same. Check the quality of the new spectrum before deleting the old one. Typically, jsNMR works best with datasets of 8k datapoints or less. On mobile devices even fewer.

Managing spectra

Obtain information on the spectral parameters for a given spectrum. This includes the spectral width (sw), reference point (ref, middle of the spectrum), number of points (np), and title.
Data stored in a jsNMR file is a self-transforming dataset, where you may use the save button to export the data into e.g. comma-separated values (CSV), a new jsNMR file, or into the raw data of the original spectrum. The latter option lets you work with the raw data in other processing software programs.
Peak lists may be exported to CSV files.
Delete the current spectrum by pressing this button. The current spectrum is highlighted by an asterisk (*) in front of its title. To select another spectrum as the current, simply click its title.
Print the current spectrum. Please be patient, it may take a while.
Display this help.

Known file formats

Currently jsNMR supports 1D NMR spectra in the following file formats For Bruker and Agilent, the data are stored in a dedicated directory. This directory must be zipped before uploading.