Comments on recently published papers reporting on “new” amino acid-based crystals in the Journal of Materials Science: Materials in Electronics

In this comment, we review six recently published papers in the Journal of Materials Science: Materials in Electronics, reporting on the growth of “new” amino acid-based crystals viz. “ l -methionine potassium hydrogen phthalate” ( 1 ), “ l -methionine barium nitrate” ( 2 ), “ l -asparagine monohydrate potassium dichromate” ( 3 ), “ l -asparagine monohydrate lithium sulphate” ( 4 ), “ l -phenylalanine lithium sulphate” ( 5 ) and “ l ‑cysteine hydrochloride monohydrate lithium sulphate” ( 6 ). All these so-called novel crystals ( 1 )–( 6 ) were characterized based on unit cell data. A critical analysis of the experimental results in these publications reveal that ( 1 ) is potassium hydrogen phthalate C 8 H 5 O 4 K, ( 2 ) is barium nitrate Ba(NO 3 ) 2 , ( 3 ) and ( 4 ) are l -asparagine monohydrate l -C 4 H 8 N 2 O 3 ·H 2 O and ( 5 ) and ( 6 ) are lithium sulphate monohydrate Li 2 SO 4 ·H 2 O, respectively, based on unit cell parameters. Taking ( 1 )–( 6 ) as examples we highlight the importance of single crystal X-ray structure determination for unambiguous characterization of new materials and suggest reporting chemical formula in the abstract of the publication.