Coincident measurement of photo-ion circular dichroism and photo-electron circular dichroism.

Two methods of laser-induced mass-selective chiral analysis based on circular dichroism have been reported in the literature: photo-ion circular dichroism (PICD) and photo-electron circular dichroism (PECD). In PICD, a difference in total ion yields upon multiphoton ionization with circular polarized light is measured, whereas in PECD, the circular dichroism is observed in the angular distribution of the photoelectrons. Here, we report the first coincident measurement of the PICD and PECD effects. A home-built photoion-photoelectron coincidence spectrometer has been used to measure both the PICD and the PECD effects simultaneously under the same measurement conditions. Pure samples of R- and S-methyloxirane have been photo-ionized using a femtosecond laser operation at 396 nm.