The local coordination structures around the doping Yb 2+ ions in sodium and potassium halides were calculated by using the first-principles supercell model.Both the cases with and without the charge compensation vacancy in the local environment of the doping Yb 2+ were calculated to study the effect of the doping on the local coordination structures of Yb 2+.Using the calculated local structures,we obtained the crystal-field parameters for the Yb 2+ ions doped in sodium and potassium halides by a method based on the combination of the quantum-chemical calculations and the effective Hamiltonian method.The calculated crystal-field parameters were analyzed and compared with the fitted results. The local coordination structures around the doping Yb 2+ ions in sodium and potassium halides were calculated by using the first-principles supercell model. The cases with and without the charge compensation vacancy in the local environment of the doping Yb 2+ were calculated to study the effect of the doping on the local coordination structures of Yb 2 +. Using the calculated local structures, we obtained the crystal-field parameters for the Yb 2+ ions doped in sodium and potassium halides by a method based on the combination of the quantum-chemical calculations and the effective Hamiltonian method. calculated crystal-field parameters were analyzed and compared with the fitted results.