The Curie temperature of lithium tantalate \({T}_{{\text{c}}}\) is influenced by the substitution of elements in the structure lattice. From the experience, the experimental results of Curie temperatures of a series of Congruent 0.2 and 0.5 mol% Nd-doped \({{\text{LiTaO}}}_{3}\) (LT) single crystals are well reproduced theoretically by combining Maaider et al new approach of ferroelectric transition with our proposed vacancy model. The substitution mechanism of Nd-doped lithium tantalate crystal is discussed in the context of the obtained chemical formulas and variation of Curie temperature.
