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Updated: Aug 21, 2026

Probe Type II Band Alignment in One-Dimensional Van Der Waals Heterostructures Using First-Principles Calculations
Published on: October 12, 2019
A graphical tool for the prediction of vicinal proton-proton 3J(HH) coupling constants
Armando Navarro-Vázquez1, Juan Carlos Cobas, Francisco Javier Sardina
1Laboratorio Integral de Dinámica y Estructura de Biomoléculas, J. R. Carracido, Unidad asociada al CSIC, Universidad de Santiago de Compostela, Spain. mestrec@usc.es
Abstract:
The easy to use and free available graphical tool MestRe-J, developed for Win-32 platforms, calculates the vicinal proton-proton coupling constants 3J(HH) from the torsion angle phi between the coupled protons for the two kinds of generalized Karplus equations developed by Altona's group as well as for equations from other authors. Besides the classical Haasnoot-de Leeuw-Altona equations, including individual substituent effects that depend on their relative Huggins's electronegativities Deltachi, the program incorporates the more recent and precise Díez-Altona-Donders equations. The substituent effects in these equations, that include effects of interactions between substituents, depend on substituent parameters lambda optimized from the 3J(HH) couplings to methyl groups. Weighted time-averaged couplings can be calculated. The equations for 3J(HH) can be solved to provide the torsion angles phi.
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