Theoretical Investigation into a Possibility of Formation of Propylene Oxide Homochirality in Space

The preferential synthesis or destruction of a single enantiomer by ultraviolet circularly polarized light (UV-CPL) has been proposed as a possible triggering mechanism for the extraterrestrial origin of homochirality. Herein, we investigate the photoabsorption property of propylene oxide (c-C(3)H(6)O) for UV-CPL in the Lyman-α region. Our calculations show that c-C(3)H(6)O was produced by CH(3)(+) and CH(3)CH(OH)CH(3) or C(3)H(7)(•) and O (triplet). The computed electronic circular dichroism spectra show that c-C(3)H(6)O and the intermediate (CH(3)CH(OH)CH(2)(+)) could absorb the UV-CPL originating from the Lyman-α emitter spectrum, suggesting that the photolysis of c-C(3)H(6)O or CH(3)CH(OH)CH(2)(+) upon irradiation could induce chiral symmetry breakage.