LiNbO3

Lithium niobate (O3) is a compound of niobium, lithium, and oxygen. It is a colorless solid that is insoluble in water. Its melting point is 1257 °C and its density is 4.65 g/cm³. Its CAS number is .Lithium niobate crystals have a trigonal crystal system and belongs to the 3m (C3v) crystallographic point group. Its crystal structure lacks inversion symmetry and displays ferroelectricity, the Pockels effect, the piezoelectric effect, photoelasticity, and nonlinear optical polarizability. Lithium niobate is has negative uniaxial birefringence which depends slightly on the stoichiometry of the crystal and on temperature. It is transparent for wavelengths between 350 and 5200 nanometers, and has a bandgap of around 4 eV.
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