Comparative spectrophotometric study of the complexation and extraction of tellurium with various halide ions and N,N′-di(acetoxyethyl)indocarbocyanine Original Research Article

Comparative spectrophotometric study of the tellurium(IV) complexation and extraction with various ligands (chloride, bromide, iodide), and cyanine dye – N,N′-di(acetoxyethyl)indocarbocyanine (DAIC) was realised. In the acidic medium, extractable by aromatic hydrocarbons and esters of acetic acid, tellurium(IV) ion associates are formed. The most effective were proved to be of the chloride complexes of tellurium. The optimum conditions were found: 4.0–5.5 M H2SO4, 1.25–3.0 M LiCl, and (0.5–2.0)×10−4 M DAIC. The molar absorptivity are (4.30–11.2)×104 l mol−1 cm−1 in reference to extractant. The iodide complexes are unsuitable for practical use. A novel extraction spectrophotometric procedure for tellurium determination in semiconductor thin films was developed.