Optical activity of BSO crystals doped with Cr, Mn and Cu
Optical activity of BSO crystals doped with Cr, Mn and Cu
复制标题
DOI：
10.1016/s0925-3467(99)00069-5
复制
发表时间：
1999-11-01
影响因子：
3.9
通讯作者：
Veleva, M
中科院分区：
文献类型：
--
作者：
Tassev, V;Gospodinov, M;Veleva, M
研究了光致变色掺杂和光致变色跃迁对未掺杂和掺杂Cr，Mn，Cu Bi_（12）SiO_（20）（BSO）晶体光学活性的影响。结果表明，Cr使BSO在520 nm以下的旋光率ρ增大70-80%，在长波区则减小40-50%。Mn在480-700 nm范围内使BSO的ρ降低约3-4%，而Cu在相同范围内使其增加约7-8%。讨论了OA与吸收的关系。结果使我们假设Cr 3+占据Bi 3+四面体（Td）位置，而Mn 4 +/5+占据Si四面体位置。Cu ~（2+）对BSO的ρ值有相反的影响，说明Cu ~（2+）优先取代BSO中的Si。在共掺杂的情况下，显然，Al 3+主要从其Bi 3 +-Td M-位置换Cr 3+。在BSO：P的情况下，结果毫无疑问地表明Cr 3+取代了P5+。(C)1999 Elsevier Science B. V.保留所有权利。
The influence of both photochromic doping and photochromic transitions on the optical activity (OA) of undoped and doped Cr, Mn and Cu Bi12SiO20 (BSO) crystals is studied. The results show that Cr strongly increases the optical rotatory power rho of BSO up to 70-80% below 520 nm and decreases it (with about 40-50%) at the long-wavelength region. Mn decreases rho of BSO: with about 3-4% in the range 480-700 nm, whereas Cu increases it with about 7-8% in the same range. The relation between OA and absorption is discussed. The results lead us to the assumption that Cr3+ occupies Bi3+-tetrahedral (Td) positions, while Mn4+/5+ occupies Si-tetrahedral positions. The opposite influence of Cu2+ on rho of BSO suggests that the Cu2+-ion preferentially replaces Si in BSO. In the co-doping cases, obviously, Al3+ predominately displaces Cr3+ from its Bi3+-Td M-sites. In the case of BSO:P, the results undoubtedly indicate that Cr3+ displaces P5+. (C) 1999 Elsevier Science B.V. All rights reserved.