*3.3.3. Sn0.95Mo0.05Se*

We have prepared a series of molybdenum-alloyed SnSe samples at various concentrations, from 1% up to 30% Mo. According to the change of lattice parameters, Mo clearly enters the SnSe structure. However, the dependence of any of the properties studied (Seebeck coefficient, electrical conductivity, unit-cell volume) vary non-monotonously, thus the use of Mo as an alloying element is questionable. Without more detailed structural studies it is impossible to assess whether Mo indeed incorporates at the nominal compositions into SnSe. For 5% Mo-doped SnSe, the temperature-dependent Seebeck coefficient is shown in **Figure 9a**. The Seebeck coefficient is positive and reaches a maximum of 400 μV/K around 700 K. While the samples are rather resistive at room temperature, we observed an abrupt increment of the electrical conductivity at 800 K, reaching values up to perhaps 10,000 S/m (not shown).
