Sensing of toxic Lewisite (L<sub>1</sub>, L<sub>2</sub>, and L<sub>3</sub>) molecules by graphdiyne nanoflake using density functional theory calculations and quantum theory of atoms in molecule analysis
Sidra Khan, Hasnain Sajid, Khurshid Ayub, Tariq Mahmood
Abstract
Abstract Promising sensor applications of graphdiyne for various gases and toxic molecules have extensively been studied; however, similar studies for the detection of chemical warfare agents (CWA) are not reported. Here, we report the adsorption of Lewisites (L 1 , L 2 , and L 3 ), on graphdiyne nanoflake (GDY) using density functional theory (DFT) ωB97XD/6‐31+G (d,p) method. Our results show that Lewisite molecules are preferably physiosorbed at the triangular portion of GDY nanoflake. In particular, the binding of L 3 (3‐chlorovinyl arsine) on GDY nanoflake is thermodynamically favorable than L 1 (1‐chlorovinylarsonous dichloride) and L 2 (2‐chlorovinylarsonous chloride). Symmetry adopted perturbation theory (SAPT0) analysis reveals that the least contribution of repulsive exchange component is present in case of L 2 @GDY complex. Further, the smallest HOMO‐LUMO energy gap, appreciable charge transfer (NBO), and largest red shift in ultraviolet‐visible (UV‐Vis) spectrum are also in accord with the higher %sensitivity of graphdiyne toward L 2 . Quantum theory of atom in molecule (QTAIM) analysis is performed to get insight into the noncovalent interactions. Therefore, it is predicted that the sensitivity of GDY nanoflake is potentially high for Lewisite especially for L 2 .