http://irgu.unigoa.ac.in/drs/handle/unigoa/5624 2026-04-27T14:39:33Z 2026-04-27T14:39:33Z Petrosyan, A.M. Srinivasan, B.R. http://irgu.unigoa.ac.in/drs/handle/unigoa/7842 2026-04-24T06:23:12Z 2026-01-01T00:00:00Z

Comments on "growth mechanism and physicochemical properties of L-threonine silver nitrate (LTSN) single crystal for frequency doubling and optical limiting applications" Petrosyan, A.M.; Srinivasan, B.R. The authors of a recent publication (Moses et al. in: J. Mater. Sci.: Mater. Electron. 37:307, 2026) report having grown and studied a new crystal "L-threonine silver nitrate" (LTSN) by the slow evaporation solution growth method. In this letter to the Editor, many points of criticism concerning the synthesis and characterization of the so-called LTSN crystal are described to prove that it is a material of unknown composition.

2026-01-01T00:00:00Z Petrosyan, A.M. Srinivasan, B.R. http://irgu.unigoa.ac.in/drs/handle/unigoa/7815 2026-03-30T10:11:04Z 2025-01-01T00:00:00Z

On the Existence of Triglycine Acetate, Triglycine Phosphate, Triglycine Oxalate and Triglycine Formate Petrosyan, A.M.; Srinivasan, B.R. The authors of a recent paper (Cryst. Res. Technol. 2022, 57, 2100130) report to have grown crystals of triglycine acetate (TGAc) by slow evaporation of an aqueous solution containing glycine and acetic acid in 3:1 molar ratio. The infrared spectrum and unit cell data of the so-called TGAc crystal confirm that it is, in fact, Alpha-glycine. The non-formation of any TGAc is due to no chemical reaction occurring between glycine and acetic acid. Another publication (Cryst. Res. Technol. 2022, 57, 2100262) describes the growth and characterization of a so-called triglycine oxalate (TGO) crystal. The unit cell data and infrared spectrum of the TGO crystal reveal that the crystal grown is, in fact, the well-known glycinium hydrogen oxalate. A critical analysis of the publications reporting on the growth of triglycine phosphate (TGP) and triglycine formate (TGF) crystals reveals that these are not what the authors claim them to be. Despite their names, the TGAc or TGP or TGO or TGF crystals are not analogs of the triglycine sulfate (TGS) crystal but serve as examples to highlight the importance of single-crystal structure refinement to avoid improper characterization.

2025-01-01T00:00:00Z Petrosyan, A.M. Thamotharan, S. Srinivasan, B.R. http://irgu.unigoa.ac.in/drs/handle/unigoa/7814 2026-03-30T10:08:41Z 2025-01-01T00:00:00Z

Comments on "influence of procion red dye doping on the structural, dielectric and optical properties of diglycine phthalic acid single crystals for nonlinear optical applications" Petrosyan, A.M.; Thamotharan, S.; Srinivasan, B.R. The title paper (J Mater Sci: Mater Electron 35 1265 (2024)) reports on the growth, characterization, properties of novel organic single crystals of "diglycine phthalic acid (DGP)" and Procion Red doped "diglycine phthalic acid (RDGP)". Many points of criticism, concerning the crystal growth and experimental data are highlighted in this communication to prove that the so-called DGP and RGDP crystals are improperly characterized materials. DGP and RGDP crystals are examples, which demonstrate that characterization of new materials based on unit cell data leads to erroneous conclusions.

2025-01-01T00:00:00Z Srinivasan, B.R. Petrosyan, A.M. http://irgu.unigoa.ac.in/drs/handle/unigoa/7813 2026-03-30T10:06:10Z 2024-01-01T00:00:00Z

Does a "glycine magnesium chloride" crystal exist? Srinivasan, B.R.; Petrosyan, A.M. The authors of a recently published paper (J Mol Struct 1277 (2023) 134,839) report to have newly grown seeds of "glycine magnesium chloride" (GMC) crystal by slow evaporation of an aqueous solution containing equimolar ratios of glycine and magnesium chloride. A critical analysis of the unit cell data and infrared spectrum of the so-called GMC crystal reveals the total absence of magnesium chloride, as these correspond to the Gamma-modification of glycine. In this letter to the Editor, we prove that all papers reporting on so-called GMC, "coumarin doped GMC" CDGMC, and "methylene blue dye doped GMC" MDGMC crystals, are erroneous as the material studied in all cases is Gamma-glycine. Hence, the quantum mechanical studies on the non-existent GMC, CDGMC and MDCMG crystals have no scientific value.

2024-01-01T00:00:00Z