Cis–trans configuration‐dependent electronic, optical, and lattice thermal transport properties of pentagonal monolayer MPS (M = Ni, Pd, Pt)

Pentagonal two‐dimensional materials provide unusual coordination environments that can give rise to structure‐dependent electronic and transport properties. Here, we investigate four optimized configurations, cis ‐NiPS, cis ‐PdPS, trans ‐PdPS, and trans ‐PtPS, focusing on the influence of cis / trans atomic arrangements. All four structures are energetically bound and dynamically and mechanically stable, with generally robust finite‐temperature behavior. The electronic character is strongly configuration dependent: among the four dynamically stable configurations considered, cis ‐NiPS and cis ‐PdPS exhibit metallic behavior, whereas trans ‐PdPS and trans ‐PtPS are semiconducting. HSE06 calculations yield an indirect band gap of 0.93 eV for trans ‐PdPS, with quasi‐direct‐gap characteristics, and a direct band gap of 1.05 eV for trans ‐PtPS. The two semiconducting trans materials also show distinct optical responses, with trans ‐PdPS exhibiting lower‐energy absorption extending toward the visible region and trans ‐PtPS showing predominantly ultraviolet absorption. In addition, both trans materials exhibit strongly suppressed in‐plane lattice thermal transport, particularly trans ‐PtPS. These results demonstrate that cis / trans structural configuration provides an effective means of tuning the electronic, optical, and phonon‐transport properties of pentagonal MPS (M = Ni, Pd, Pt) monolayers, highlighting their potential for optoelectronic and nanoscale thermal‐management applications.