Theoretical study of the selective control of photoionization and photodissociation

Present work have investigated the selective control of the optimal path and the population transfer rate for photoionization and photodissociation of CO and NO by using time-dependent wave packet dynamics method. Combing the calculated transition properties, it has determined the optimal route of photoionization that is CO X1Σ+→E1П(v’ = 0)→CO+ X2Σ+ by two-photon, which the laser wavelength corresponds to 110 nm and 202 nm, respectively. By changing the laser parameters, we found that, when the intensity is 6.7 × 1013W/cm2 and duration is 100fs, not only the transfer rate of ionized population reaches maximum 99.1%, but also the purity is very high. For photodissociation of NO molecule, the projection of initial wave function of ground state on the quantum state v’ = 8 of excited state A2Σ+ is calculated. It showed that the yield of photodissociation is about 43% by using guassian pulse with intensity 1 × 1014W/cm2 and duration 56fs. However, not only promoting earlier t = 25fs of reaction time but also making the yield increases up to 57% by the positive chirp pulse. These main information suggest a scheme for the feasibly photochemical reaction and will provide an important reference for further theoretical and experimental researches. •The optimal route of photoionization was determined CO X1Σ+→E1П→CO+X2Σ+ of two-photon ionization.•When intensity of femtosecond laser is 6.7×1013W/cm2, the transfer rate of ionized population reaches 99.1%.•For photodissociation of NO at A2Σ+ state, the yield on v’=8 level by using positive chirp is higher than guassian pulse.