Electronic Properties and Stability of Single-Layer and Multilayer Cu<sub>3</sub>(HHTP)<sub>2</sub> Metal–Organic Frameworks
Pedro H. Souza, Walter Orellana
Abstract
The stability and electronic properties of conductive single-layer and multilayer Cu 3 (HHTP) 2 metal–organic frameworks (MOFs), with HHTP = hexahydroxytriphenylene, composed of Cu(II) ions coordinated by the oxygen atoms of HHTP ligands, are investigated by using noncollinear-spin density functional theory calculations. For the single-layer structure, we examined distinct magnetic configurations: ferromagnetic (FM), frustrated magnetic (FMI), and antiferromagnetic (AFM). Our analysis identifies a noncollinear AFM ground state, with the collinear FM and FMI states being 84 and 88 meV higher in energy, respectively. The noncollinear AFM state exhibits distinct conductivity properties, characterized by flat and quadratic bands, while the collinear FM and FMI states display Dirac electrons, providing evidence for a topological kagome magnet. For multilayer structures, we assess three stacking geometries: perfectly aligned (AA), slight dislocation (AA′), and high dislocation (AB). Our findings indicate that AA′ is the most stable structure, followed by AA and AB at 0.3 and 0.8 eV higher in energy, respectively. The interlayer binding energy is calculated at 10 meV/Å 2 for both AA and AA′. All three stacking configurations exhibit the FM ground state, attributed to interplane interactions. Additionally, the stability of single-layer Cu 3 (HHTP) 2 was tested by ab initio molecular dynamics simulations, which demonstrated both its flexibility and strength. Overall, this work provides insights into the stability and conductive properties of this MOF, suggesting potential applications in nanoelectronic devices.