The vibrational properties of $2H\text{−}{\mathrm{TaSe}}_{2-x}{\mathrm{S}}_x$ $(0\le x\le 2)$ single crystals were probed using Raman spectroscopy and density functional theory calculations. The end members revealed two out of four symmetry-predicted Raman active modes, together with the pronounced two-phonon structure, attributable to the enhanced electron-phonon coupling. Additional peaks become observable due to crystallographic disorder for the doped samples. The evolution of the $E_{2g}^2$ mode Fano parameter reveals that the disorder has a weak impact on electron-phonon coupling, which is also supported by the persistence of two-phonon structure in doped samples. As such, this research provides thorough insights into the lattice properties, the effects of crystallographic disorder on Raman spectra, and the interplay of this disorder with the electron-phonon coupling in $2H\text{−}{\mathrm{TaSe}}_{2-x}{\mathrm{S}}_x$ compounds.

中文翻译：

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拉曼光谱证明2H−TaSe2−xSx(0≤x≤2)中无序竞争和电子声子耦合

的振动特性$2H\text{-}{\mathrm{硒化钽}}_{2-X}{\mathrm{S}}_X$ $（0\le X\le 2）$使用拉曼光谱和密度泛函理论计算来探测单晶。端部成员揭示了四种对称预测拉曼活性模式中的两种，以及明显的双声子结构，这归因于增强的电子声子耦合。由于掺杂样品的晶体学无序，可以观察到额外的峰。的演变${乙}_{2G}^2$模式 Fano 参数表明，无序对电子-声子耦合影响较弱，掺杂样品中双声子结构的持久性也支持了这一点。因此，这项研究提供了对晶格性质、晶体无序对拉曼光谱的影响以及这种无序与电子-声子耦合的相互作用的深入见解。$2H\text{-}{\mathrm{硒化钽}}_{2-X}{\mathrm{S}}_X$化合物。