POLARIZED RAMAN-SPECTRUM OF A SINGLE-CRYSTAL OF AZT

Polarized Raman scattering measurements have been made of a single cry stal of AZT (3'azido-3'-deoxythymidine) by the use of a Raman microsco pe with the 488.0 nm exciting beam from an argon-ion laser. The AZT cr ystal belongs to the space group P2(1) (monoclinic), and Raman scatter ing intensities, corresponding to the aa, bb, c'c', and bc' components of the crystal Raman tensor, have been determined for each prominent Raman band. Here, c'-axis was defined as an axis perpendicular to the a-axis in the ac plane. From these experimental data, and on the basis of the known crystal structure, localized Raman tensors have been det ermined, which are assignable to azido vibrations at 2088 and 1259 cm( -1), to thymine at 1666, 1392, 1238, 771, and 495 cm(-1) and deoxyribo se vibrations at 870, 849 and 739 cm(-1). The knowledge of these local ized Raman tensors are considered to be useful for probing the orienta tion of the AZT molecule in a biological system involving it. (C) 1996 John Wiley & Sons, Inc.