The authors of the published title paper (Bull. Mater. Sci. 2020 43 17) claim to have grown a resorcinol-doped potassium hydrogen phthalate (RKHP) crystal by a slow evaporation method. It was reported that the organic dopant enhances the second harmonic generation efficiency (SHG) of potassium hydrogen phthalate (KHP). In this letter to Editor, many points of criticism concerning the crystal growth and the characterization of the so-called RKHP crystal are discussed to prove that the published original paper is erroneous.

中文翻译：

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评论：掺杂KHP单晶的透光率和倍频效率显着提高

已发表的标题论文 ( Bull. Mater. Sci . 2020 43 17) 的作者声称已经通过缓慢蒸发方法生长了间苯二酚掺杂的邻苯二甲酸氢钾 (RKHP) 晶体。据报道，有机掺杂剂提高了邻苯二甲酸氢钾 (KHP) 的二次谐波产生效率 (SHG)。在这封给编辑的信中，对所谓的RKHP晶体的晶体生长和表征的许多批评点进行了讨论，以证明所发表的原始论文是错误的。