Does a glycine sodium nitrite crystal exist?

TL;DR

This paper critically examines previously reported glycine sodium nitrite crystals and reveals that the claimed crystal is actually gamma-glycine, questioning the validity of several other glycine-based crystals.

Contribution

It clarifies the true identity of the glycine sodium nitrite crystal and questions the authenticity of other reported glycine crystals, correcting the scientific record.

Findings

Glycine sodium nitrite is actually gamma-glycine.

Several other reported glycine crystals are dubious.

The study emphasizes the importance of proper characterization.

Abstract

The glycine sodium nitrite crystal reported by Khandpekar and Pati in the paper entitled, Synthesis and characterisation of glycine sodium nitrite crystals having non linear optical behaviour, Opt Commun 285, 2012 288-293 is actually gamma-glycine. In addition, we show that glycine barium ammonium nitrate, glycine sodium zinc sulfate, glycine barium calcium nitrate, glycine acetamide and glycine dimer are dubious crystals.