Humidity effect on hydration of CsLiB6O10 nonlinear optical crystal: X-ray diffraction study

Abstract Cesium lithium borate crystals (CLBO) grown from melt were kept under the relative humidity of 15–77%. At RH 45% or lower, water molecules are incorporated into CLBO structure resulting in symmetry reduction from I 4 ¯ 2 d to I 4 ¯ without the loss of crystal quality. At higher humidity, crystal degradation is caused by the presence of liquid water on its surface as a result of capillary condensation.