SrWO_4晶体中F型色心电子结构的研究

Study on electronic structures of SrWO_4 crystals containing F type color centers

运用相对论的密度泛函离散变分法(DV-Xα)研究了SrWO4晶体中F型色心的电子结构.计算结果表明,F和F+心在禁带中引入了新的施主能级;从施主能级到导带底的电子跃迁能分别是1.858,2.14 eV,这分别与669,581 nm的吸收带相对应.由此说明SrWO4晶体中669,581 nm吸收带起源于晶体中的F和F+心.

The electronic structures of SrWO4 crystals containing F-type color centers were studied within the framework of the fully relativistic self-consistent Dirac-Slater theory, using a numerically discrete variational DV-X（α） method. The calculation reveals that both the F and F^＋ centers in SrWO4 have donor energy levels within the forbidden band. The electronic transition energies from the donor level to the bottom of the conduction band are 1. 858 eV and 2.14 eV, corresponding to the 669nm and 581 nm absorption bands respectively. It is therefore predicted that the 581- 669 nm absorption bands originate from the F and F＋ centers in SrWO4 crystal.