Fachbereich Physik, Universität Osnabrück, D-49069 Osnabrück, Germany.
J Phys Chem A. 2010 Aug 19;114(32):8444-9. doi: 10.1021/jp104437n.
The ground state of H-center systems for the SrF(2) crystal is simulated with two different arrangements, which are oriented along either [100] or [111] axes. The calculations are based on hybrid Hartree-Fock and density functional theory exchange functionals by using Becke's three-parameter method combined with the nonlocal correlation functionals of Perdew and Wang. The energy difference between H centers with different orientations shows that the H center oriented in the [111] direction in alkaline earth fluorides is the most stable configuration. The geometric relaxations of the neighboring atoms surrounding the H centers are presented. The combination energy of an H center and the formation energy of the related F-H pair in both alkaline earth fluorides are discussed. We report also the electronic structure of the H center systems. The effective charges and spins of the substitutional and interstitial fluorine atoms show that the hole is located at the interstitial fluorine in the system with the [111] orientation of the H center. The band structures are illustrated. With the help of studying the total and partial density of states, the constituents of the defect bands are clarified.
采用两种不同的取向，即[100]或[111]轴，对 SrF(2)晶体的 H 中心体系的基态进行了模拟。计算基于混合 Hartree-Fock 和密度泛函理论交换泛函，使用 Becke 的三参数方法结合 Perdew 和 Wang 的非局部相关泛函。不同取向 H 中心之间的能量差表明，在碱土氟化物中，沿[111]方向取向的 H 中心是最稳定的构型。给出了 H 中心周围相邻原子的几何弛豫。讨论了碱土氟化物中 H 中心的结合能和相关 F-H 对的形成能。我们还报告了 H 中心体系的电子结构。取代和间隙氟原子的有效电荷和自旋表明，在 H 中心沿[111]取向的体系中，空穴位于间隙氟原子处。说明了能带结构。通过研究总态和部分态密度，澄清了缺陷带的组成。
