Current status of the proposals for unification of notations and guidelines for data presentation in the EMR Area: Blueprint for future actions

The tremendous development of the electron magnetic resonance (EMR), i.e., electron paramagnetic resonance (EPR), electron spin resonance (ESR), and related spectroscopic techniques, and their applications in a number of fields is accompanied by a rather messy situation in the underlying theoretical framework. This is especially true concerning the EPR of transition ions in crystals, where an abundance of notations and lack of widely accepted clear definitions of the basic theoretical concepts characterize the current situation. As a consequence, proliferation of a number of terminological misconceptions and incorrect relations for the zero-field splitting parameters has taken place. Major problems detrimental for the future of EMR as well as the efforts aimed at alleviating these problems are reviewed. Rationales for coordinated activities in three major directions are outlined. This includes unification of spin Hamiltonian notations, unification of EMR nomenclature, and making better use of the various categories of data generated during EMR studies.

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