Evaluation of newly synthesized phosphoramide derivatives as mild steel anti-corrosions using experimental and theoretical approaches

•Three new phosphoramide derivatives were synthesized, and characterized using spectroscopy techniques.•The inhibition and adsorption performances of these compounds on mild steel corrosion were investigated.•PDP studies demonstrated that the titled compounds behaved as mixed-type inhibitors.•DFT computations and MD simulations were accomplished to confirm experimental results.•These compounds formed strong Cl-H•••N-P hydrogen bonds with the HCl.