Ueda T, Shinozaki K, Ushizawa K, Yimit A, Tsuboi M
Department of Chemistry, Meisei University, Tokyo, Japan.
Nucleic Acids Symp Ser. 1997(37):95-6.
Polarized Raman scattering measurements have been made of a single crystal of 5-iodouracil by the use of a Raman microscope with the 488.0 nm excitation. The crystal belongs to space group P2(1) (monoclinic), and Raman scattering intensities, corresponding to the a'a', bb, cc, a'b and bc components of the crystalline Raman tensor, have been determined for each prominent Raman band, where a' is the axis perpendicular to the c axis in the ac plane. From these experimental results, the shapes and orientations of the Raman scattering tensors have been derived for 6 base vibrations in the 5-iodouracil molecule. By comparing these tensors with those for thymine and pseudouridine vibrations, discussions were made of the polarizability oscillations caused by the normal vibrations localized in the pyrimidine base.
利用配备488.0 nm激发光源的拉曼显微镜对5-碘尿嘧啶单晶进行了偏振拉曼散射测量。该晶体属于空间群P2(1)（单斜晶系），已针对每个突出的拉曼谱带确定了与晶体拉曼张量的a'a'、bb、cc、a'b和bc分量相对应的拉曼散射强度，其中a'是ac平面中垂直于c轴的轴。根据这些实验结果，推导了5-碘尿嘧啶分子中6种碱基振动的拉曼散射张量的形状和取向。通过将这些张量与胸腺嘧啶和假尿苷振动的张量进行比较，对嘧啶碱基中局域的正常振动引起的极化率振荡进行了讨论。
