Modulating the molecular third-order optical nonlinearity by curved surface of carbon skeleton

Curved π bowl compounds represent another class of the completely conjugated materials with quantum dot nature. Non-equivalent hybridisation type from rim to hub carbon atoms in curved π bowl compound triggers anisotropic physical properties. With density functional method (CAM-B3LYP) and response theory calculations, curved π bowl compounds exhibit large radial and axial component ratio for its polarisability and the second hyperpolarisability. More importantly, they possess larger effective mass second hyperpolarisability (γ^mass) and nondiagonal components (γ_xxyy) compared to C₆₀. Except the static properties, the dispersion characters of dynamic cubic response of curved π bowl compounds have been analysed in large frequency range.