Given the severe environmental and health risks posed by heavy metal pollutants such as mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr), and arsenic (As), the development of highly efficient and selective capture materials is critically important.This study explores the molecular structural characteristics of complexes formed by substituting the central palladium atom in nitrogen-heterocyclic carbene complexes with mercury (Hg), cadmium (Cd), lead (Pb), chromium (Cr), and arsenic (As). For all the complexes, the simulated infrared and ultraviolet-visible spectra, Wiberg bond indices, as w...