In 1993 Kuz’minov and Osiko pointed out the ‘disturbance�?of stoichiometry in LN crystals is principally mainly because of the lack of oxygen in Nb2O5, applied being a raw content First soften (Czochralski approach) [186]. Appropriately, depending on its output know-how, niobium pentoxide can undertake a wide range of compositions Nb2O5−x.