Nutrition Evidence Library Staff Director: Joanne M. Spahn, MS, RD, FADA Joan M. G. Lyon, MS, RD Jean M. Altman, MS Donna Blum-Kemelor, MS, RD, LD Eve V. Essery, PhD Thomas V. Fungwe, PhD Patricia Carrera MacNeil, MS, LN, CNS Mary M. McGrane, PhD Julie Obbagy, PhD, RD “
“The task of setting up a complicated spin system for a solid state NMR or EPR simulation is a noted test of perseverance: an aspiring theorist
would find himself juggling nested time-dependent tensor rotations in half a dozen ad hoc conventions , , , , ,  and , struggling with Euler angle singularities ,  and  and trying to visualize interactions that occur in direct products Venetoclax price Dabrafenib of Lie algebras  and . Function libraries , , ,  and , command-line , ,  and  and interactive simulation tools for spin systems are available, but convenient point-and-click visualization and editing tools for setting up complex calculations are in their infancy. More importantly, no standards exist (whether by ISO, IUPAC or even a consensus) on a universal spin system
description format that would be applicable across all types of Magnetic Resonance spectroscopy – every major simulation package has its own spin system specification requirements. Of the existing formats, the Pople convention  only deals with NMR and the latest IUPAC recommendations only go as far as listing reasonable chemical shift and shielding tensor reporting styles  and . At the time of writing, the task of setting up a complicated spin system for simulation
still amounts to manual parsing of unintuitive conventions and hand-coding of the associated tensor transformations. In this communication, we suggest a simple and general XML  and  format for spin system description that is the result of broad consultations within NMR and EPR communities. many The format does not attempt to introduce or change any of the current interaction specification conventions , , , , , , , , , ,  and , but instead incorporates them as special cases and options into a common framework. SpinXML format is human-readable, extensible and easy to edit, both manually and automatically. We also describe a graphical user interface that was designed to facilitate the setting up of complicated spin systems and is capable of importing interaction data from electronic structure theory programs as well as producing input files for spin dynamics simulation packages. This section describes elements, types and attributes specified by the SpinXML schema file that is included into the Supplementary Information and available for download from the Spinach library website (http://spindynamics.org).