  We have investigated temperature-dependent behaviors of electronic structure
and resistivity in a mixed-valent golden phase of SmS, based on the dynamical
mean-field theory band structure calculations. Upon cooling, the coherent Sm
4$f$ bands are formed to produce the hybridization induced pseudogap near the
Fermi level, and accordingly the topology of Fermi surface is changed to
exhibit a Lifshitz-like transition. The surface states emerging in the bulk gap
region are found to be not topologically protected states but just typical
Rashba spin-polarized states, indicating that SmS is not a topological Kondo
semimetal. From the analysis of anomalous resistivity behavior in SmS, we have
identified universal energy scales, which characterize the Kondo/mixed-valent
semimetallic systems.
