MUPen2DTool: A new Matlab Tool for 2D Nuclear Magnetic Resonance relaxation data inversion

Abstract

A great variety of applications requires to process two-dimensional NMR (2DNMR) data to obtain information about the materials properties. In order to face the increasing request for software to easily process 2DNMR data, in (Bortolotti et al. (2019) [1]), the authors released Upen2dTool, an open source MATLAB software tool implementing nonnegatively constrained uniform penalty locally adapted L2norm-based regularization for 2DNMR data inversion. This paper presents MUPen2DToola new open-source MATLAB software tool implementing an unconstrained multipenalty regularization method based on L2and L1norms. The new software MUPen2DTooloutperforms Upen2dTool since the implemented uniform multipenalty method allows to compute very accurate 2DNMR data inversion at reduced computational cost. By means of MUPen2DTool, the user can choose among several types of NMR experiments, and the free software provides codes that can be used and extended easily. Furthermore, a MATLAB interface makes it easier to include users own data. The practical use is demonstrated in the reported examples of both synthetic and real NMR data.

Keywords

• 2D NMR data inversion
• Inversion of exponential Laplace-type kernels
• Multiple penalty regularization
• Uniform penalty principle
• Adaptive regularization