Comments on the paper "Synthesis and characterization of inorganic nonlinear optical material: Potassium sodium hydroxide borate hydrate (KSB) single crystal"

Abstract

The authors of the title paper (Mater. Lett. 188 (2017) 156-158) claimed to have grown potassium sodium hydroxide borate hydrate (KSB) single crystal and reported its mechanical properties in a subsequent paper (Mater. Lett. 215 (2018) 165-168). In this letter, many points of criticism concerning the crystal growth, structure characterization and interpretation of the spectral and thermal data of the so-called KSB crystal are described to prove that it is a dubious material.