Departamento de Matemática y Física, Facultad de Ciencias Químicas, INFIQC, Universidad Nacional de Córdoba, Ciudad Universitaria, Córdoba, Argentina.
J Phys Condens Matter. 2013 Mar 20;25(11):115304. doi: 10.1088/0953-8984/25/11/115304. Epub 2013 Feb 14.
Optical properties of TiO(2) nanoclusters (with more than 30 TiO(2) units) were calculated within a fully atomistic quantum dynamic framework. We use a time dependent tight-binding model to describe the electronic structure of TiO(2) nanoclusters in order to compute their optical properties. We present calculated absorption spectra for a series of nanospheres of different radii and crystal structures. Our results show that bare TiO(2) nanoclusters have the same adsorption edge for direct electronic transition independently of the crystal structure and the nanocluster size. We report values of the adsorption edge of around 3.0 eV for all structures analyzed. In the present work we demonstrate that, for small clusters, both the direct transition absorption edge and the blue shifting phenomena are masked by thermal disorder.
在全原子量子动力学框架内计算了具有超过 30 个 TiO2 单元的 TiO2 纳米团簇的光学性质。我们使用含时紧束缚模型来描述 TiO2 纳米团簇的电子结构，以计算它们的光学性质。我们给出了一系列不同半径和晶体结构的纳米球的计算吸收光谱。我们的结果表明，裸露的 TiO2 纳米团簇对于直接电子跃迁具有相同的吸收边缘，与晶体结构和纳米团簇尺寸无关。我们报告了所有分析结构的吸收边缘约为 3.0eV。在目前的工作中，我们证明了对于小团簇，直接跃迁吸收边缘和蓝移现象都被热无序掩盖了。
