Skobeltsyn Institute of Nuclear Physics, M V Lomonosov Moscow State University, Moscow, Russia.
J Phys Condens Matter. 2011 Sep 14;23(36):365501. doi: 10.1088/0953-8984/23/36/365501. Epub 2011 Aug 19.
Calculations of the band structure, partial densities of states and optical spectra of permittivity, reflectivity and absorption of perfect ZnMoO(4) crystal were performed using the full-potential linear-augmented-plane-wave method. It is shown that the calculated reflectivity spectra reproduce the main features of corresponding experimental spectra in the fundamental absorption region. The bandgap value of ZnMoO(4) is estimated as E(g) = 4.3 eV. Peculiarities of luminescence excitation spectra corrected for near-surface losses and losses on reflectivity are discussed, taking into account the results of the calculations. It is found that the energy structure of the lower part of conduction band is manifested in the excitation spectra of the intrinsic luminescence. The excitation spectra in the region 4.3-8.0 eV are formed by band-to-band electronic transitions mainly within the molybdate groups MoO(4)(2-), whereas electronic states of Zn(2+) cations are not directly involved into the excitation processes. It is shown that the structure of the intrinsic luminescence excitation spectrum depends on the temperature and mechanisms of the structure modification are discussed.
采用全势能线性缀加平面波方法，计算了完美 ZnMoO(4) 晶体的能带结构、部分态密度和介电常数、反射率和吸收率的光学谱。结果表明，计算得到的反射率谱在基本吸收区域再现了相应实验谱的主要特征。ZnMoO(4) 的能带隙值估计为 E(g) = 4.3 eV。考虑到计算结果，讨论了经近表面损耗和反射损耗修正后的发光激发谱的特点。结果表明，导带下部的能量结构在本征发光的激发光谱中表现出来。4.3-8.0 eV 区域的激发光谱主要由 MoO(4)(2-) 钼酸盐基团内的带-带电子跃迁形成，而 Zn(2+) 阳离子的电子态并未直接参与激发过程。结果表明，本征发光激发光谱的结构取决于温度，并且讨论了结构改性的机制。
