An IR absorption measurement of SiO2/Si nanowires made by thermal evaporation was conducted. In comparison with SiO2 nanoparticles, enhancement absorption of SiO2/Si nanowires around 1130 cm(-1) was observed. This enhancement was considered to result from: (1) the interface effect of the open structure of chainlike SiO2/Si nanowires; (2) the vibration of an interstitial oxygen atom in a silicon single-crystalline core of nanowire; and. The longitudinal optical (LO) modes of Si-O-Si stretching in an amorphous SiO2 outer shell of SiO2/Si nanowires were also discussed. (C) 2003 Elsevier B.V. All rights reserved.