8. Nickel oxide, NiO, is doped with lithium oxide, Li2O, to form LixNi1xO withi[o] the sodium chloride structure. (a) Derive the form of the Heikes equation for the variation of Seebeck coefficient, , with the degree of doping, x. The following table gives values of versus log[(1x)/x] for this material. (b) Are the current carriers holes or electrons? (c) Estimate the value of the constant term k/e. Data adapted from E. Antolini, Mater. Chem. Phys., 82, 937-948 (2003)