The structural properties of liquid nitromethane(NM)confined in single-walled carbon nanotubes(SWNTs)was explored by molecular dynamics simulations towards the stabilization of energetic materials through nanoscale confinement.[1-4] Ordered structures with unique intermolecular orientations can be formed under the SWNT confinement governed by the van der Waals attractions of NM and SWNT,and the dipole-dipole interactions of NM,which is strongly dependent on the diameters of SWNT(see Figure 1).Furthermore,the local mass density of confined NM is higher than that of bulk NM.The novel structures of NM reported herein may potentially lead to controlled decomposition pathway and energy release of energetic materials.