Study on the Contribution of the Charge Transfer Excited States in Ba2MgGe2O7∶Cr4+ Crystal to g Factor
WU Xiao-xuan1, 2, 3,ZHENG Wen-chen2, 3
1. Department of Physics, Civil Aviation Flying Institute of China, Guanghan 618307, China 2. Department of Material Science, Sichuan University, Chengdu 610064, China 3. International Centre for Materials Physics, Chinese Academy of Sciences, Shenyang 110016, China
Abstract：A complete high-order perturbation formula of g factor for cubic 3d2 MX4 clusters was established. In the formula, not only the contributions of the crystal-field (CF) mechanism (which is related to the CF excitations) to the g-shift Δg(=g-gs), but also the contributions of the charge-transfer (CT) mechanism (related to CT excitations) were considered. Using the formula, the g factor of Ba2MgGe2O7∶Cr4+ was calculated. The result was in agreement with the observed value. It was found that the calculated ΔgCT due to the charge-transfer mechanism is opposite in sign and about 38% in magnitude, compared with the calculated ΔgCF due to the crystal-field mechanism. So, for a high valence 3dn ion in crystals, the reasonable explanation of g factor should take into account the contributions of both crystal-field and charge-transfer mechanisms.
Key words：Electron paramagnetic resonance;g factor;Charge transfer mechanism;Crystal-and ligand-field theory;Ba2MgGe2O7 crystal
吴晓轩1, 2, 3,郑文琛2, 3. Ba2MgGe2O7∶Cr4+晶体中荷移激发态对g因子贡献的研究[J]. 光谱学与光谱分析, 2007, 27(01): 8-11.
WU Xiao-xuan1, 2, 3,ZHENG Wen-chen2, 3 . Study on the Contribution of the Charge Transfer Excited States in Ba2MgGe2O7∶Cr4+ Crystal to g Factor . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2007, 27(01): 8-11.
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