Interaction of B12N12 nano-cage with cysteine through various functionalities: A DFT study

Abstract

The adsorption behavior of amino acid cysteine over the pure B12N12 nano-cluster has been investigated using density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. Interaction between the cluster and the amino acid has been explored through all the four functional groups; hydroxyl (-OH), carboxyl (-COOH), amine (-NH2), and thiol (-SH) of the acid. The zwitterionic form of the amino acid has also been taken into consideration while studying the adsorption of amino acid on the cluster surface. The nature of interaction between the two has been exhaustively explored in terms of adsorption energy, nearest atom distance, optical and electronic properties as well as vibrational frequencies analysis. The affinity of cluster to bind more than one amino acid has been established for amino acids that are present as dippetide as well as for two distinct cysteine molecules.