Nonlinear optical response of Li n ClK (n = 1–6) superalkali clusters

Abstract The geometrical structures, stabilities, electronic properties and nonlinear optical response of the halogen doped bimetallic Li n ClK ( n = 1–6) clusters were studied within the density functional theory. Based on the dissociation energy, second order energy difference and GH-L (HOMO-LUMO gap), the Li n ClK ( n = 2, 4, 6) clusters are more stable. According to their ionization energies, the clusters can be classified as a superalkali. From the NBO analysis, the clusters are excess electron systems. The obtained first static hyperpolarizability ( β o ) values are in the range of 1.56 × 10 4 − 4.33 × 10 4 au while the second static hyperpolarizability vary within 2.47 × 10 6 au to 13.9 × 10 6 au for the Li n ClK ( n = 1–6) superalkalis that are slightly higher than the nonlinear optical response of halogen doped monometallic clusters. More importantly, the Li 5 ClK is transparent in the deep UV region ( λ < 300 nm) among the superalkalis indicating that the Li 5 ClK superalkali can be a candidate structure as new member of NLO materials.