A density functional theory computational investigation on geometries and electronic properties of the inner hollow (GaP)_n (n = 1–38) nanomaterials

Geometries and properties of (GaP)_n (n = 1–38) nanocages are systematically investigated at the B3PW91 level. Particularly, the inner spaces, HOMO–LUMO gaps, and charge-transfers of the stable (GaP)_n are generally increased as the sizes of (GaP)_n being extended. The (GaP)_n geometries undergo a structural variation with the size of clusters being increased. The medium size clusters present the hollow globular forms with large surface effect, based upon the calculated fragmentation energies and averaged atomic binding energies. The relative stabilities of (GaP)_n nanoclusters are discussed. The stable (GaP)₆ and (GaP)₁₂ clusters are predicted, which can self-assemble 2D bilayer GaP nanosheets with possible stronger quantum efficiencies for optoelectronic devices or energy nanomaterials. The calculated energy gaps of (GaP)_n show they are obviously width energy gap nanoclusters and have size dependent absorption wavelengths. The ionic bonds in (GaP)_n are discussed and dominate gradually chemical bonding as the size of (GaP)_n being increased, indicating that large-sized (GaP)_n prefer to capture CO2 molecules and have properties of ionic semiconductors.