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A comparative study of thermal properties of SmFeAsO, SmFeAs(O 0.93 F 0.07 ) and SmFeAs(O 0.85 F 0.15 ) samples is presented. Specific heat and thermal conductivity show clear evidences of the spin density wave (SDW) ordering below T SDW~1 35 K in undoped SmFeAsO. At low level of F-doping, SmFeAs(O 0.93 F 0.07 ), SDW ordering is suppressed and superconducting features are not yet optimally developed in both specific heat and thermal conductivity. At optimal level of F-doping SmFeAs(O 0.85 F 0.15 ) anomalies related to the superconducting transition are well noticeable. By a compared analysis of doped and undoped samples we conclude that, despite F-doping modifies definitely the electronic ground state, it does not substantially alter phonon and electron parameters, like phonon modes, Sommerfeld coefficient, electro-phonon coupling. The analysis of the thermal conductivity curves provides an evaluation of SDW and superconducting energy gap, showing that phonons can suitably probe features of electronic ground state.

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