在pH为3．5的邻苯二甲酸氢钾-盐酸缓冲溶液中，在聚乙烯醇存在下，钼（Ⅵ）与邻苯二酚紫（PV）形成的配阴离子[Mo（PV）2]2-与结晶紫（CV）阳离子结合形成的离子缔合物具有较强的共振瑞利散射光谱。其最强共振瑞利散射峰位于647 nm处。基于共振瑞利散射峰的逐渐增强，建立了测定痕量钼（Ⅵ）的共振瑞利散射法。该方法钼（Ⅵ）质量浓度在0．1~0．6 mg/L范围内与共振瑞利散射光强度呈良好的线性关系，检测限为1．5×10-4 mg/L ，可用于水样中钼的测定。%In potassium hydrogen phthalate-hydrochloric acid buffer solution (whose pH=3.5) and in the presence of polyvinyl alcohol (PVA),Mo (Ⅵ) reacts with pyrocatechol violet (PV) to form a complex anion [Mo (PV)2]2-, which can combine with crystal violet (CV) to form ion association compounds with strong resonance rayleigh scattering spectra. The strongest resonance rayleigh scattering peak is located at the position of 647 nm. On the basis of gradual enhancement of resonance rayleigh scattering peak ,the resonance rayleigh scattering technique has been established for the determination of trace molybdenum (Ⅵ). When the mass concentration of molybdenum (Ⅵ) is in the range of 0.1-0.6 mg/L,it shows a good linear relationship with resonance rayleigh scattering light intensities,and the detection limit is 1.5 ×10-4 mg/L. Therefore,this technique can be used for the determination of molybdenum (Ⅵ) in the water samples.
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