Figure 1

The polynomial interpolation of a set of TEPs in4 at (top) equidistant nodes and (bottom) Chebyshev nodes: (left) Seebeck coefficient \(\alpha (T)\), (center) electrical resistivity \(\rho (T)\), (right) thermal conductivity \(\kappa (T)\). The black dots denote the raw data points. The exact curve is assumed to be a quadratic spline for Seebeck coefficient and a linear spline for electrical resistivity and thermal conductivity. The green dots (the red dots) denote data points at 13 equidistant nodes (Chebyshev nodes) resampled from the exact curve.