研究了在表面活性剂聚乙烯醇(PVA₁₂₄)存在下,硝酸介质中,汞与碘化物形成络阴离子后与罗丹明B(RhB)形成可溶性多元离子缔合物,在595nm处有最大吸收,0～5μgHg2⁺／25ml范围内服从比耳定律,其表观摩尔系数为7．36×10⁵,桑德尔灵敏度为2．7×10^-4μg／cm²,回收率为98．0％～103．0％,RSD＜3％.

A spectrophotometric method for the determination of trace amounts of mercury(Ⅱ)was described based on the formalion of a complicated ion-association complex of Hg(Ⅱ)-1-Rhodamine B in the presence of polyvinyl alcohol. The maximum absorption of the ion-association complex was at 595nm.Beer's law was obeyed for mercury(Ⅱ)in the range of 0~5μg/25ml. The apparent molar absorptivity was 7．36×10⁵L/mol·cm.The recovery of mercury was 97. 0%~103.0%,RSD<3%. The procedure was highly selective with good sensitivity and the result of de;ermination was saUSfactory.