  Combining the bond-order-length-strength (BOLS) and bonding and binding
energy (BB) models with density functional theory (DFT) calculations, we
studied the atomic bonding and binding energy behavior of Bi atoms adsorbed on
the Li(110) surface. We found that the Bi atoms adsorbed on the Li(110) surface
form two-dimensional (2D) geometric structures, including letter-, hexagon-,
galaxy-, crown-, field-, and cobweb-shaped structures. Thus, we obtained the
following quantitative information: (i) the field-shaped structure can be
considered the bulk structure; (ii) the field-shaped structure of Bi atom
formation has a 5d energy level of 22.727 eV, and in the letter shape
structure, this energy is shifted to values greater than 0.342 eV;and (iii) the
Bi/Li(110) heterojunction transfers charge from the inner Li atomic layer to
the outermost Bi atomic layer. In addition, we analyzed the bonding and
electronic dynamics involved in the formation of the Bi/Li(110) heterojunctions
using zone-selective electron spectroscopy technology. This work provides a
theoretical reference for the fine tuning of binding energies and chemical
bonding at the interfaces of 2D metallic materials.
