In this paper, we study the influence of platinum (100) surface morphology on the tangential-momentum accommodation coefficient with argon using a molecular dynamics method. The coefficient is computed directly by beaming Ar atoms onto the surfaces and measuring the relative momentum changes. The wall is maintained at a constant temperature and its interaction with the gas atoms is governed by the Kulginov potential. To capture correctly the surface effect of the walls and the atoms' trajectories, the quantum Sutton-Chen multibody potential is employed between the Pt atoms. The effects of wall surface morphology, incident direction, and temperature are considered in this work and provide full information on the gas-wall interaction.