TY - JOUR
AU - Yang, Xiaohui
AU - Bao, Jin-Ke
AU - Lou, Zhefeng
AU - Li, Peng
AU - Jiang, Chenxi
AU - Wang, Jialu
AU - Sun, Tulai
AU - Liu, Yabin
AU - Guo, Wei
AU - Ramakrishnan, Sitaram
AU - Kotla, Surya Rohith
AU - Tolkiehn, Martin
AU - Paulmann, Carsten
AU - Cao, Guang-Han
AU - Nie, Yuefeng
AU - Li, Wenbin
AU - Liu, Yang
AU - van Smaalen, Sander
AU - Lin, Xiao
AU - Xu, Zhu-An
TI - Commensurate Stacking Phase Transitions in an Intercalated Transition Metal Dichalcogenide
JO - Advanced materials
VL - 34
IS - 6
SN - 0935-9648
CY - Weinheim
PB - Wiley-VCH
M1 - PUBDB-2022-00563
SP - 2108550 -
PY - 2022
N1 - Waiting for fulltext
AB - Intercalation and stacking-order modulation are two active ways in manipulating the interlayer interaction of transition metal dichalcogenides (TMDCs), which lead to a variety of emergent phases and allow for engineering material properties. Herein, the growth of Pb-intercalated TMDCs–Pb(Ta<sub>1+x</sub>Se<sub>2</sub>)<sub>2</sub>, the first 124-phase, is reported. Pb(Ta<sub>1+x</sub>Se<sub>2</sub>)<sub>2</sub> exhibits a unique two-step first-order structural phase transition at around 230 K. The transitions are solely associated with the stacking degree of freedom, evolving from a high-temperature (high-T) phase with ABC stacking and R3m symmetry to an intermediate phase with AB stacking and P3m1, and finally to a low-temperature (low-T) phase again with R<sub>3</sub>msymmetry, but with ACB stacking. Each step involves a rigid slide of building blocks by a vector [1/3, 2/3, 0]. Intriguingly, gigantic lattice contractions occur at the transitions on warming. At low-T, bulk superconductivity with Tc ≈ 1.8 K is observed. The underlying physics of the structural phase transitions are discussed from first-principle calculations. The symmetry analysis reveals topological nodal lines in the band structure. The results demonstrate the possibility of realizing higher-order metal-intercalated phases of TMDCs and advance the knowledge of polymorphic transitions, and may inspire stacking-order engineering in TMDCs and beyond.
LB - PUB:(DE-HGF)16
C6 - pmid:34871466
UR - <Go to ISI:>//WOS:000732521900001
DO - DOI:10.1002/adma.202108550
UR - https://bib-pubdb1.desy.de/record/474173
ER -