Multiplet structures emeralds

First-principles calculation for multiplet structure of emerald... 

First-Principles Calculation for Multiplet Structure of Emerald... 

In the present paper, we applied the newly developed DV-ME method to the calculations of the multiplet structure in emerald, in which dilutely doped Cr + ions substitutes for aluminium ions and work as a color active center. 

First-Principles Calculation for Multiplet Structure of Emerald at DV sample points (22), such as,... 

For the calculation of the multiplet structure of emerald, we used three types of model clusters, shown in Fig. 1 (1) [Cr06] in hypothetical Oh symmetry, (2) [Cr06] in D3 symmetry, and (3) [CrBe,t Al3Si6042] 2" including cations making up of the host lattice. The model (1) is a model where the trigonal distortion is removed to have a cubic symmetry for a comparison with the model... 

The effect of intrinsic trigonal distortion on the multiplet structures of ruby and emerald... 

In solid-state laser materials, such as ruby (chromium doped alumina, AljOjiCr " ) (1) and emerald (chromium doped beryl, Be,Al,(Si03)5 Cr ) (2), transitions between multiplets of impurity states are utilized. These states mainly consist of 3d orbitals of the impurity chromium ions. For the analysis of these multiplet structures, the semi-empirical ligand-field theory (LFT) has been frequently used (3). However, this theory can be applied only to the high symmetry systems such as O, (or T ). Therefore, the effect of low symmetry is always ignored in the analysis based on the LFT, although most of the practical solid-state laser materials actually possess more or less distorted local structures. For example, in ruby and emerald, the impurity chromium ions are substituted for the aluminum ions in the host crystals and the site symmetry of the aluminum ions are C, in alumina and D, in beryl. Therefore, it is important to clarify the effect of low symmetry on the multiplet structure, in order to understand the electronic structure of ruby and emerald. 

Effect of Intrinsic Trigonal Distortion on the Multiplet Structures of Ruby and Emerald 99... 

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