The type-VIII clathrate Ba₈Ga₁₆Sn₃₀ (BGS) is a promising thermoelectric material with a cage-guest structure. The failure mechanisms behind the tetrahedrally bonded framework, which are vital for understanding the structure - mechanical property relationship, are still unrevealed. Here we conduct DFT calculations to investigate the intrinsic mechanical behavior of BGS. BGS has the ideal strength of 2.65 GPa under (100)/[010] shearing. The fast stretching and breakage of Sn-Sn bond give rise to the sudden failure of Ga-Sn bond, resulting in the collapse of void space and the structural damage. Under [100] tension, the structural failure is due to the breakage of Ga-Sn bonds that are nearly parallel to the tensile direction. Besides, Ga-Sn bonds are dominant for maintaining the local rigidity since they contribute the vast majority of structural resistance.

VIII型包合物Ba ₈ Ga ₁₆ Sn ₃₀ (BGS)是一种很有前途的笼客体结构热电材料。四面体键合框架背后的失效机制对于理解结构 - 力学性能关系至关重要，但仍未揭示。在这里，我们进行 DFT 计算以研究 BGS 的内在机械行为。BGS的理想强度为2.65 (100)/[010] 剪切下的 GPa。Sn-Sn键的快速拉伸和断裂导致Ga-Sn键突然失效，导致空隙空间坍塌和结构损坏。在[100]张力下，结构失效是由于几乎平行于拉伸方向的Ga-Sn键断裂。此外，Ga-Sn 键在维持局部刚性方面占主导地位，因为它们贡献了绝大多数的结构阻力。