The present work addresses the students in chemistry, chemical engineering of the environment, as well as the specialists in chemistry of the phosphorus and the organophosphate compounds, in Hydrometallurgy both at the industrial level and at the level of the scientific research. This work aims to be a guide for the chemistry of the agent's complexants of types phosphonic & aminophosphonic acids, consisted widely used in the liquid-liquid extraction for the extraction of metals and rare earths, in the proceeding of ores and in the aqueous effluent treatments for the recovery and the valuation of rare earths, N-C-P in medicinal chemistry, pesticides/herbicides and water-decontamination systems, organometallic complexes: MOF, gas absorption, proton conductivity and Magnetic shielding tensors.