The Raman spectra of carbon nanotubes prepared by catalytic (C-CNT) and d.c. are discharge (D-CNT) methods are reported. A previously unnoticed third-order Raman peak at ca. 4248 cm(-1) was observed in the Raman spectrum of D-CNT. The Raman features of D-CNT and C-CNT are similar to those of highly oriented pyrolytic graphite (HOPG) and active carbon, respectively. The data also suggest that the increase in disorder in D-CNT compared with HOPG is doe to structural defects in D-CNT. (C) 1997 by John Wiley & Sons, Ltd.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:A1997WZ29900011&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701SpectroscopySCI(E)91ARTICLE5369-3722
