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研究了Ｍｏ（Ⅵ）与Ｔｉｒｏｎ的反应，发现在ｐＨ４．０的ＨＡｃ－ＮａＡｃ介质中形成１：１配合物，该配合物在２５２ｎｍ、３１５ｎｍ有两个吸收峰，而在可见光区无吸收峰。测得ε２５２＝６．９×１０￣３Ｌ·ｍｏｌ－１·Ｃｍ－１，ε３１５＝３．５×１０３Ｌ·ｍｏｌ－１·Ｃｍ－１。据此建立了测定Ｍｏ（Ⅵ）的方法，在２５２ｎｍ和３１５ｎｍ处的线性范围分别为１．６×１０－６ｍｏｌ·Ｌ－１～２．Ｏ×１０－４ｍｏｌ·Ｌ－１和３．２×１０－４ｍｏｌ·Ｌ－１～２．０×１０－４ｍｏｌ·Ｌ－１。检出限分别为８．Ｏ×１０－７ｍｏｌ·Ｌ－１和１．６×１０－６ｍｏｌ·Ｌ－１．ＰＯ＿４￣３＋、ＳｉＯ＿３￣２－对测定无干扰，而Ｗ（Ⅵ）、Ｖ（Ⅴ）、Ｆｅ（Ⅲ）等有干扰。该法试用于有机磷合钼聚多酸盐样品的测定，结果满意，方法回收率９６％～１０２％，变异系数≤１．ｌ％（ｎ＝１２）。
The reaction of Mo (Ⅵ) with Tiron was studied. It was found that 1: 1 complex was formed in HAc-NaAc medium at pH4.0. The complex has two absorption peaks at 252nm and 315nm and no absorption peak in the visible region. Ε252 = 6.9 × 10 -3 L · mol -1 · cm -1 and ε 315 = 3.5 × 103 L · mol -1 · cm -1 were measured. The method for the determination of Mo (Ⅵ) has been established. The linear range at 252 nm and 315 nm is 1.6 × 10 -6 mol·L -1. O × 10-4mol·L-1 and 3.2 × 10-4mol·L-1 ~ 2.0 × 10-4mol·L-1. Detection limits were 8. O × 10-7mol·L-1 and 1.6 × 10-6mol·L-1. PO_4 ~ 3 +, SiO_3 ~ 2-no interference on the determination, and W (Ⅵ), V (Ⅴ), Fe (Ⅲ) and other interference. The method was applied to the determination of organophosphorus molybdenum polyacid samples with satisfactory results. The method recoveries ranged from 96% to 102% and the coefficients of variation were ≤1. l% (n = 12).