Spectrophotomftric determination of germanium with 1.1'-dianthrimide

In conc. sulfuric acid a coloured complex is formed between germanium and 1.1'-dianthrimide, which has an absorption maximum at 660 mμ, and can be used for the spectrophotometric determination of germanium. The method is applicable at concentrations up to at least 6 mg Ge per 100 ml. Among the more common ions serious interference is caused by boron and fluoride. Thc interference from fluoride is probably due to attack on the glass and release of boron.