International Journal of Academic and Applied Research (IJAAR)   Year: 2021 | Volume: 5 | Issue: 6 | Page No.: 33-38 The Effect of Doping Talha Gum Arabic with Iodine on the Absorption Coefficient and Energy Gap Nuha Hassan Kinash, Mubrarak Dirar Abd-Alla, Ahmed Al Hassan Alfaki , Abdalskhi .S.M.Hamed. Abstract: Five samples from Talha Gum Arabic were doped with iodine having concentrations (0.1, 0.2, 0.3, 0.4, 0.5 ppm).The energy gap were studied using ultraviolet spectrophotometer. The d-spacing and the crystal nano sizes were studied using X-ray diffraction device. Increasing iodine concentration decreases nano crystal size and d-spacing. The increase of iodine concentration decreases the energy gap to take the values (2.364, 2.356, 2.352, 2.345, and 2.339 eV).