Kagomé metals are widely recognized, versatile platforms for exploring topological properties, unconventional electronic correlations, magnetic frustration, and superconductivity. In the RV₆Sn₆ family of materials (R = Sc, Y, Lu), ScV₆Sn₆ hosts an unusual charge density wave ground state as well as structural similarities with the AV₃Sb₅ system (A = K, Cs, Rb). In this work, we combine Raman scattering spectroscopy with first-principles lattice dynamics calculations to reveal phonon mixing processes in the charge density wave state of ScV₆Sn₆. In the low temperature phase, we find at least four new peaks in the vicinity of the V-containing totally symmetric mode near 240 cm⁻¹ suggesting that the density wave acts to mix modes of P6/mmm and \(R\bar{3}m\) symmetry - a result that we quantify by projecting phonons of the high symmetry state onto those of the lower symmetry structure. We also test the stability of the short-range ordered density wave state under compression and propose that both physical and chemical pressure quench the effect. We discuss these findings in terms of symmetry and the structure-property trends that can be unraveled in this system.

Kagomé 金属是广泛认可的多功能平台，用于探索拓扑特性、非常规电子相关性、磁挫败和超导性。在R V ₆ Sn ₆系列材料（R = Sc、Y、Lu）中，ScV ₆ Sn ₆具有不寻常的电荷密度波基态以及与A V ₃ Sb ₅系统（A = K，铯、铷）。_{在这项工作中，我们将拉曼散射光谱与第一原理晶格动力学计算相结合，揭示了ScV 6} Sn ₆电荷密度波态中的声子混合过程。在低温阶段，我们在 240 cm ^-1附近的含 V 完全对称模式附近发现了至少四个新峰，表明密度波起到了混合P 6/ m m m和\(R\ bar{3}m\)对称性 - 我们通过将高对称性状态的声子投影到低对称性结构的声子上来量化的结果。我们还测试了压缩下短程有序密度波态的稳定性，并提出物理和化学压力都会淬灭该效应。我们从对称性和可以在该系统中阐明的结构-性能趋势方面讨论这些发现。