In addition, the DOS effective masses closely depend on the carrier effective masses, summarized in Table . Sc2Si2Te6 displays larger and more anisotropic effective masses for both electrons and holes compared to Sb2Si2Te6, as expected, which is also represented by the smaller Fermi velocities of Sc2Si2Te6 compared to Sb2Si2Te6 (Figure ). Therefore, the heightened band degeneracy, combined with increased carrier effective masses, is anticipated to result in a significantly higher Seebeck coefficient for Sc2Si2Te6. Table . Hole and electron effective masses (me) of Sb2Si2Te6 and Sc2Si2Te6 were calculated using parabolic fitting in sumo with the HSE06+SOC functional. The corresponding k-point path is given in parentheses.