jVisualizer can help reconstruct the patterns found in your chemistry experiment, coupling patterns in NMR spectroscopy, which are sometimes not easy to understand. In a second step you can type in the chemical shifts and calculate the coupling constants. jVisualizer is also a good tool for teachers to demonstrate how complex coupling patterns are formed. The source code is also available. What's New: Version 2.5.1 adds some changes with layout problems in the main window on MacOS X with com.apple.mrj.swing.MacLookAndFeel | 
