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perature solvent evaporation led to the separation results for a new and promising solution-grown NLO material, L-histidine tetrafluoroborate h[(C3N2H4)CH2CH(NH3)(CO2)]1BF42; HFBj. HFB is an example of a semiorganic NLO material, in which the high optical nonlinearity of a purely or-ganic material is combined with the favorable me-chanical and thermal properties of an inorganic.1,2 Much recent work3,4 has demonstrated that organic crystals can have very large nonlinear susceptibili-ties compared with inorganic crystals, but their use is impeded by their low optical transparencies, poor mechanical properties, low laser damage thresholds, and an inability to produce and process large crys-tals. Purely inorganic NLO materials typically hav