Monoclinic non-standard crystal-field parameters (CFPs) obtained by optical spectroscopy reanalyzed based on standardization idea.
CFP analysis for laser crystals Nd3+: LuAlO3; Nd3+: BaY2F8; RE3+ ions in Gd2O3, Y2O3, Er2O3, Pr3+, Sm3+, Gd3+; Er3+: LaF3; Er3+: YAlO3.
Several confusing problems clarified.
Alternative CFPs determined by us may improve reliability of final fitted CFPs.