First-principles studies on the electronic and optical properties of Fe-doped potassium dihydrogen phosphate crystal

In this work, we performed first-principles calculations on the electronic structure and optical properties of the perfect and Fe-doped potassium dihydrogen phosphate (KDP). The partial substitution of P in perfect KDP with Fe (Fe-KDP) induced defect states in the band gap of Fe-KDP, narrowing its band gap to 3.8 eV (the corresponding optical absorption wavelength is 355 nm). We also see the impurity peaks induced by the Fe-doped point defects in dielectric function, absorb spectrum, L(omega), k(omega) and R(omega) curves. All of the results can provide the good basis for deeply understanding the optical properties of the KDP crystal. (C) 2017 Elsevier B.V. All rights reserved.