Abstract
Morphological diagram with respect to crystal growth of L-ascorbic acid (C6H8O6; so-called vitamin C) from methanol solution on a flat glass dish is presented. Varying humidity and initial concentration of L-ascorbic acid in methanol solution, the following three distinct kinds of growing patterns have been observed: homogeneous disk, concentric ring and dendrite. In addition, in higher concentration clearly faceted small single crystals grow in any humidity less than 90%. Crossovers from one pattern to another were observed, too.