Fig. 4: Fitting results of the one-particle potentials with a theoretical potential function.
From: Evidence of tuned anharmonicity in the thermoelectric material Cu2-xS
The obtained coefficients in the theoretical potential function (Eq. 6) are shown as follows: a harmonic coefficients α(S) and α(Cu); b anisotropic anharmonic coefficients, including the 3rd-order coefficient |β|(Cu) and the fourth-order coefficient δ(S); c the isotropic anharmonic fourth-order coefficient γ(S); and d anharmonicity ratios |β/α|(Cu) and |δ/α|(S). The error bars represent standard deviations estimated from least squares fitting in Igor-Pro 8 software.
