Thermal Conductivity Calculation with the Molecular Dynamics Direct Method I: More Robust Simulations of Solid Materials

Comparison and Evaluation of Spectral Energy Methods for Predicting Phonon Properties

“…With the Green-Kubo or non-equilibrium direct methods, molecular dynamics (MD) simulations can be used to predict thermal conductivity, but only in a classical (i.e., high-temperature) framework [8,17,[24][25][26][27][28][29][30]. Because the analysis in these two MD-based methods is performed at the system level, no information about the phonons is obtained.…”

Finite-size effect of the thermal conductivity in one dimensional chain

“…However, in our study, the slops (as well as the intercepts) of the two limit cases are not equal, with ). Reasoning that the inequality of the slopes (β 1 and β 2 ), the dependence (1/κ versus 1/L) must involve nonlinear terms in general cases and which has been founded by recent studies [17,22,28,29]. To general cases, the derivative d d To solve the equation, l=l(ω) must be known.…”

“…Qualitatively, it is easy to see that the rapid nonlinear temperature drops [22,29,30,46] in boundary layers are chief reasons for the decrease of thermal conductivities with decreasing system size. As a result, a smaller temperature gradient in the middle regions, a smaller heat current, and a smaller thermal conductivity than ideal cases emergence.…”

Predicting Phonon Properties From Equilibrium Molecular Dynamics Simulations

“…The Green-Kubo and direct methods can be applied to crystals, alloys, amorphous solids, and fluids. Recent work has focused on computational aspects, notably accounting for size effects, quantifying and reducing uncertainty, and reducing computational time [56,[61][62][63][64][65][66][67][68].…”

“…detailed suggestions on what system sizes to use and how long to run the simulations to optimize use of the direct method [65,66].…”