Quasi-one-dimensional GaSeI nanochain with a noncentrosymmetric helical chain structure have recently been synthesized, offering a unique platform for exploring mechanical and thermal properties in low-dimensional materials. Here, we develop a neuroevolution potential (NEP) for GaSeI nanochain based on ab initio molecular-dynamics (AIMD) simulations, enabling systematic investigation of their mechanical response and lattice thermal transport. Stress-strain analysis reveals that GaSeI nanochain exhibits mechanical strength comparable to carbon nanotubes, with ultimate stress approaching that of graphene, indicating that, despite distinct bonding mechanisms, the material possesses high structural stability. Nonequilibrium molecular-dynamics (NEMD) calculations show that the lattice thermal conductivity is lower than that predicted by the phonon Boltzmann transport equation, due to the inherent inclusion of higher-order phonon scattering in NEMD. Thermal conductivity decreases modestly with increasing tensile strain, yet the reduction is far smaller than that observed in typical one-dimensional materials, such as carbon nanotube. This behavior arises from the weaker polar-covalent nature of Ga-Se bonds, which can buffer structural perturbations via local bond-angle adjustments, thereby maintaining robust phonon transport. These findings demonstrate that GaSeI nanochain possess both excellent mechanical stability and strain-insensitive thermal conductivity, suggesting their potential application in thermal management of flexible, stretchable, and deformable devices.
Zhang et al. (Fri,) studied this question.