采用第一原理的方法研究了Ti2GeC的电子结构和弹性性质.从电子结构中可以看出,Ti2GeC中存在着共价键、离子键和金属键3种键.在态密度和Mulliken布居分析中有赝能隙和电荷转移.还得到了体模量、杨氏模量、切变模量、泊松比和德拜温度等物理参数.各向异性参数表明了Ti2GeC在压缩和剪切上主要呈现出各向同性.
The bonding nature and elastic property of Ti2GeC are researched by first-principle study. The nature of chemical bonding can be recognized as a combination of covalent, ionic and metallic bonds from their electronic structures. Density of state and Mulliken population analysis are also explored to assess the origins of "pseudogap" and charge transfer. The bulk modulus, Young's modulus, shear modulus, Poisson's ratio and the Debye temperature are determined. The calculated anisotropy factors indicate that Ti2GeC are largely compression and shear isotropic.
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