Computer Modeling of Simple Point Defects in Rare Earth Doped Alkaline Earth Fluorides.

摘要: The results of a package FORTRAN computer programs for modelling defects in ionic crystals and fitting experimental data are described. fundamental concept the defect simulation is similar to HADES except that minimisation procedure different since designed run on small computers. As an example use this package, relative stabilities NN NNN complexes various rare earths, Ianthanum yttrium considered. First, data-fitting routine was used analyse relaxation rare-earth-doped strontium fluoride. fluoride were then conjunction with defect-simulation program determine potentials all lanthanum. Those rare-earth calcium show complex should not be observable possibly smallest earths. This implies B site Wright co-workers or RII requires another explanation. Also, barium fluoride, showing only largest earths Next, enthalpy reorientation via interstitialcy mechanism calculated In general, enthalpies larger than values. However, variation size earth reasonable agreement experiment. Finally, pressure found excellent