Clarification of the confusion concerning the crystal-field quantities vs the zero-field splitting quantities in magnetism studies: Part II—Survey of literature dealing with model studies of spin systems

For respective quantities, i.e., Hamiltonians, parameters, and energy level splittings, related to two physically distinct notions X and Y, various cases of confused terminology have been identified in literature. Referring to a quantity related actually to the notion Y using incorrectly   the name of another well-defined notion X constitutes, what may be defined for short as, the type X=YX=Y confusion. An ongoing survey of magnetism literature indicates that quantities related to zero-field splitting (ZFS) or equivalently fine structure (FS) are most often confused with those related to crystal-field (CF) or equivalently ligand field (LF). In this review the CF=ZFSCF=ZFS confusion cases, i.e., labelling actual ZFS/FS quantities as purportedly   ‘CF/LFCF/LF’ ones, appearing in magnetism studies are surveyed and clarified. Part I covers the cases occurring in literature dealing with specific compounds. In this part model studies of spin systems are surveyed. The cases of terminology mixing up actual ZFS/FS quantities with purported   CF/LF ones are identified and presented comprehensively in tabular form. To facilitate discussion, problems pertinent for the CF=ZFSCF=ZFS confusion are categorized into several groups, including origin of the two notions, physical consequences, usage of specific numerical values, invoking real magnetic spin systems, and properties of spin S=12 systems. Physical implications of this confusion for interpretation of model results are also considered. Overall implications of incorrect terminology go beyond simple semantic issues and concern possible misinterpretation of data describing various physical properties of models studied. Such terminology contributes also to misleading keyword classifications of papers in journals and scientific databases. Other types of confusion identified in survey of magnetism literature will be discussed in separate reviews.