Evolution of structure, stability, and nonlinear optical properties of the heterodinuclear CNLin (n = 1–10) clusters

•The structures and properties of the CNLin0/+ (n = 1–10) clusters are studied.•The CN triple bond is completely cleaved in the CNLi100/+ clusters.•The CNLi8 and CNLi10 clusters show considerable low VIPs and large β0 values.

The lowest-energy structures and stabilities of the heterodinuclear clusters, CNLin (n = 1–10) and relevant CNLin+ (n = 1–10) cations, are studied using the density functional theory with the 6-311 + G(3df) basis set. The CNLi6 and CNLi5+ clusters are the first three-dimensional ones in the CNLin0/+ series, respectively, and the CN group always caps the Lin0/+ moiety in the CNLin0/+ (n = 1–9) configurations. The CN triple bond is found to be completely cleaved in the CNLi100/+ clusters where the C and N atoms are bridged by two Li atoms. The CNLin (n = 2–10) clusters are hyperlithiated molecules with delocalized valence electrons and consequently possess low VIP values of 3.780–5.674 eV. Especially, the CNLi8 and CNLi10 molecules exhibit lower VIPs than that of Cs atom and can be regarded as heterobinuclear superalkali species. Furthermore, these two superalkali clusters show extraordinarily large first hyperpolarizabilities of 19,423 and 42,658 au, respectively. For the CNLin+ cationic species, the evolution of the energetic and electronic properties with the cluster size shows a special stability for CNLi2+.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (145 K)Download as PowerPoint slide