Crystal‐Field Spectra of d3,7 Ions. V. Tetrahedral Co2+ in ZnAl2O4 Spinel
Crystal‐Field Spectra of d3,7 Ions. V. Tetrahedral Co2+ in ZnAl2O4 Spinel
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DOI：
10.1063/1.1672431
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发表时间：
1969-10
影响因子：
4.4
通讯作者：
J. Ferguson;D. Wood;L. V. Uitert
中科院分区：
文献类型：
--
作者：
J. Ferguson;D. Wood;L. V. Uitert
本文研究了低温下Co ~（2+）在ZnAl_2 O_4尖晶石（锌尖晶石）四面体（Td）位的吸收光谱和荧光光谱。由此产生的能级图包括四个四重态和九个二重态，并且首先在没有自旋轨道耦合的弱场形式主义中进行了解释。在该分析中，推导出Dq = 0的“自由离子”水平，并与结晶环境影响之外的自由离子水平进行比较。晶体中静电相互作用参数F2和F4的减小是由于共价效应。第二种方法已被用来分析的精细结构的能级在强场自旋轨道形式主义。所有能带的精细结构都可以用简单的自旋-轨道分裂来解释，但是4 T1 a态的Jahn-Teller畸变的可能性不能完全消除。
Absorption and fluorescence spectra of Co2+ in the tetrahedral (Td) site of ZnAl2O4 spinel (gahnite) at low temperatures have been observed and analyzed. The resulting energy‐level diagram includes four quartet states and nine doublets, and has been interpreted first in terms of a weak field formalism without spin–orbit coupling. In this analysis the “free‐ion” levels for Dq = 0 were deduced and compared with those for a free ion outside the influence of the crystalline environment. The reduction in the electrostatic interaction parameters F2 and F4 in the crystal is due to the effect of covalency. A second approach has been used to analyze the fine structure of the energy levels in terms of a strong field spin–orbit formalism. The fine structure can be explained for all the bands on the basis of simple spin–orbit splitting, but the possibility of a Jahn–Teller distortion of the 4T1a state cannot be entirely eliminated.