Electronic and spectroscopic properties of A-series nerve agents

A-series nerve agents lack accurate experimental data on toxicity and other physicochemical properties. In this work, we computed molecular, spectroscopic, and electronic properties of the A-230, A-232, A-242, and A-262 agents employing Density Functional Theory (DFT) with the hybrid exchange-correlation B3LYP and M06-2X functionals, and the second-order Moller-Plesset Perturbation Theory. Computed infrared, Raman activity, ultraviolet-visible, electronic circular dichroism, and nuclear magnetic resonance spectra provide useful information for the accurate characterization of these agents. Electronic properties suggest that the four molecules have similar reactivities, though are less reactive than VX and VR nerve agents. Electrostatic potential surfaces and population analysis strongly indicate that A-series molecules have two electropositive centers. DFT lipophilicity values confirm these compounds' high lipophilic character, although their values are smaller than for VX and VR. These results are an important contribution for investigating new possibilities of identification, treatment, prevention and destruction/neutralization of these compounds.