The dynamics of copper intercalated molybdenum ditelluride

Abstract

Layered transition metal dichalcogenides are emerging as key materials in nanoelectronics and energy applications. Predictive models to understand their growth, thermomechanical properties and interactions with metals are needed in order to accelerate their incorporation into commercial products. Interatomic potentials enable large-scale atomistic simulations at the device level, beyond the range of applications of first principle methods. We present a ReaxFF reactive force field to describe molybdenum ditelluride and its interactions with copper. We optimized the force field parameters to describe the properties of layered MoTe2 in various phases, the intercalation of Cu atoms and clusters within its van der Waals gap, including a proper description of energetics, charges and mechanical properties. The training set consists of an extensive set of first principle calculations computed from density functional theory. We use the force field to study the adhesion of a single layer MoTe2 on a Cu(111) surface and the results are in good agreement with density functional theory, even though such structures were not part of the training set. We characterized the mobility of the Cu ions intercalated into MoTe2 under the presence of an external electric fields via molecular dynamics simulations. The results show a significant increase in drift velocity for electric fields of approximately 0.4 V/Å and that mobility increases with Cu ion concentration.

Atomic Structure of Intrinsic and Electron-Irradiation-Induced Defects in MoTe2

“…The reactive bond-order-dependent force field that supports bond breaking and bond formation was used to describe the interaction between molybdenum and tellurium atoms and also the interaction between the carbon atoms. 41 , 42 Long distance van der Waals interactions between the carbon atoms and between C–Mo and C–Te were treated with Morse potentials. All calculations were performed with Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) code.…”

“…The two graphene sheets are misoriented by ∼18 • with respect to each other, and the resulting moiré pattern periodicity is ∼14 Å. The reactive bond-order-dependent force field that supports bond breaking and bond formation was used to describe the interaction between molybdenum and tellurium atoms and also the interaction between the carbon atoms [41,42]. Long distance van der Waals interactions between the carbon atoms and between C-Mo and C-Te were treated with Morse potentials.…”

Transforming the Accuracy and Numerical Stability of ReaxFF Reactive Force Fields

“…Moreover, ReaxFF is significantly less costly than DFTB or neural network potentials . Noteworthy applications of ReaxFF include the study of combustion and fuels chemistry, − heterogeneous catalysis, − nanotechnology, − enzymatic reactions, high-energy materials, − and aqueous phase chemistry, − among others.…”

Exploring the Compositional Ternary Diagram of Ge/S/Cu Glasses for Resistance Switching Memories

“…The algorithm to optimize the force field is reported in the Supporting Information, Figure S9. This procedure has been used previously to optimize ReaxFF parameters for Cu/MoTe 2 …”

“…This procedure has been used previously to optimize ReaxFF parameters for Cu/MoTe 2 . 58 ■ RESULTS AND DISCUSSION Initial Parameters and Charge Equilibration. We started from Ge (and H) parameters proposed by Psofogiannakis and van Duin.…”