Single-layer (SL) transition-metal chalcogenides (TMCs) represent an important family of two-dimensional (2D) materials that have attracted intensive research attention recently. It has been established that many TMCs are polymorphic that can exist in different crystal structures and correspondingly exhibit diverse physical properties. Discovery of new structural phases of a crystal is of great scientific and practical importance. In this work, we report a new polymorph of SL-TMC, i.e. SL-Mo 5 Te 8 , attained by molecular-beam epitaxy (MBE). Like the 1 H -MoTe 2 , it possesses the hexagonal symmetry but a much larger unit cell with a basis containing as many as 39 atoms (15 Mo and 24 Te). We call it the variational hexagonal (v1 H ) phase. Coincidently, it may be viewed also as one containing the highest density possible of mirror-twin domain boundaries (MTBs) in an otherwise pristine 1 H -MoTe 2 . Electronically, it is metallic...

中文翻译：

---

单层Mo 5 Te 8 ―层状过渡金属硫属元素化物的新多晶型物

单层（SL）过渡金属硫族化物（TMC）代表着重要的二维（2D）材料族，最近已引起了广泛的研究关注。已经确定，许多TMC是多晶型的，可以存在于不同的晶体结构中并相应地表现出多种物理性质。发现晶体的新结构相具有重大的科学和实践意义。在这项工作中，我们报告了通过分子束外延（MBE）获得的SL-TMC的新多晶型，即SL-Mo 5 Te 8。像1 H -MoTe 2一样，它具有六边形对称性，但具有更大的晶胞，其基础包含多达39个原子（15 Mo和24 Te）。我们称其为变六边形（v1 H）相。巧合的是，它也可以被视为在其他原始的1 H-MoTe 2中包含尽可能高的镜像双畴边界（MTB）的密度。电子上，它是金属的...