中文摘要：

比较LDA和GGA两种方法在计算Y2O3的结构、介电和振动性质方面的不同。对Y2O3的结构进行了优化,运用密度泛函微扰理论计算了Y2O3在布里渊区中心点的声子频率、光频介电张量、零频介电张量和波恩有效电荷,并与其它文献数据进行对比。研究表明,对于不同性质的计算,LDA和GGA各有优势。

英文摘要：

The structural,vibrational and dielectric properties of Y2O3 are calculated with both the local-density approximation（LDA）and the generalized gradient approximation（GGA）.Results of electronic dielectric tensors,static dielectric tensors,Born effective charges and phonon frequencies at the Brillouin zone center are reported in the framework of density functional perturbation theory.Group theory is adopted to identify these phonon modes at the center of Brillouin zone.Comparisons are made between values from LDA and GGA,indicating that for the calculations of different properties,LDA and GGA have their own advantages.