F Mahmoudi - Department of Chemistry, University of Sistan and Baluchestan, Zahedan, P. O. Box ۹۸۱۳۵-۶۷۴, Iran
M Shahraki - Department of Chemistry, University of Sistan and Baluchestan, Zahedan, P. O. Box ۹۸۱۳۵-۶۷۴, Iran

Herein, it has been described a study on the inclusion complex formation and molecular interactions between nerve agent sarin and scavenger β-cyclodextrin (β-CD) by performing quantum mechanical calculations including PM۶ semi-empirical and density functional theory (DFT) in vacuum and in water. Two models (model ۱ and model ۲) of complexation were taken into consideration. First, the docking process was investigated between sarin and β-CD using the PM۶ method to find the most stable structure. Next, the energy decomposition, the global reactivity descriptors, and finally, natural bond orbital (NBO) calculations on the most stable complex were continued with the DFT computations. The obtained results clearly indicated that the formed complexes are energetically favored with or without solvent. Analysis of the electronic chemical potential as a reactivity descriptor showed that the encapsulation process is spontaneous. The NBO calculations confirmed the existence of hydrogen bonding between sarin and β-CD in both vacuum and water.

Sarin, β-Cyclodextrin, Inclusion complex, DFT