ABSTRACT
As grown and vacuum annealed lithium niobate single crystals have been studied by means of x-ray diffraction and IR spectroscopy. The vacuum annealed crystals of black color have shown the existence of new phase different of as grown crystals by bigger interplane distances. IR study has shown that new phase exists in the form of droplets inside the as grown LiNb03 matrix. Experimental results point on the ilmenite structure of the new phase.
