西南师范大学学报（自然科学版）
西南師範大學學報（自然科學版）
서남사범대학학보（자연과학판）
JOURNAL OF SOUTHWEST CHINA NORMAL UNIVERSITY
2014年
5期
22-26
,共5页
光学性质%热力学性质%电子结构
光學性質%熱力學性質%電子結構
광학성질%열역학성질%전자결구
optical properties%thermodynamic properties%electronic structure
采用基于第一性原理的赝势平面波法系统计算了LiNbO3晶体的电子结构、晶格振动和热力学性质，分析了掺杂抗光散射离子Mg2＋和Sc3＋对光学性质的影响．结果表明：室温时LiNbO3晶体的恒容热容为22 J/mol · K ，600 K时，徳拜温度达到772．LiNbO3晶体中掺入Mg2＋或Sc3＋离子，导致光学性质发生明显改变，极限介电常数由4.8降低到3.7，极限折射率 n0由2.2降低到1.9．
採用基于第一性原理的贗勢平麵波法繫統計算瞭LiNbO3晶體的電子結構、晶格振動和熱力學性質，分析瞭摻雜抗光散射離子Mg2＋和Sc3＋對光學性質的影響．結果錶明：室溫時LiNbO3晶體的恆容熱容為22 J/mol · K ，600 K時，徳拜溫度達到772．LiNbO3晶體中摻入Mg2＋或Sc3＋離子，導緻光學性質髮生明顯改變，極限介電常數由4.8降低到3.7，極限摺射率 n0由2.2降低到1.9．
채용기우제일성원리적안세평면파법계통계산료LiNbO3정체적전자결구、정격진동화열역학성질，분석료참잡항광산사리자Mg2＋화Sc3＋대광학성질적영향．결과표명：실온시LiNbO3정체적항용열용위22 J/mol · K ，600 K시，덕배온도체도772．LiNbO3정체중참입Mg2＋혹Sc3＋리자，도치광학성질발생명현개변，겁한개전상수유4.8강저도3.7，겁한절사솔 n0유2.2강저도1.9．
First‐principles calculations of electronic structure ,lattice dynamic and thermodynamic proper‐ties of LiNbO3 have been performed in plane‐wave pseudopotential method .The effect of doping anti‐scat‐tering ions M g2+ and Sc3+ on optical properties has been analyzed .It is show n that the heat capacity at constant volume of the LiNbO3 crystal is 22 J/mol · K at room temperature and the Debye temperature reachs 772 at 600 K .The optical properties are changed obviously when the anti‐scattering ions Mg2+ or Sc3+ are doped in LiNbO3 crystal ,the zero frequency limit of dielectric constant is reduced from 4 .8 to 3 . 7 and the zero frequency limit of refractive index n0 is decreased from 2 .2 to 1 .9 .
