文摘
In this work, the time-dependent density functional theory (TD-DFT) method was used to study the electronic excited-state dynamics of the hydrogen-bonded p-Cresol–NH3–H2O complex. The intermolecular hydrogen bonds O1–H1···N and C–O1···H2 were demonstrated by the optimized geometric structure of the hydrogen-bonded p-Cresol–NH3–H2O complex. The infrared spectra (IR spectra) of the hydrogen-bonded p-Cresol–NH3–H2O complex in the ground and excited states were also calculated by using the density functional theory (DFT) and TD-DFT methods. It is demonstrated that hydrogen bond O1–H1···N can be strengthened while hydrogen bond C–O1···H2 is weakened upon photoexcitation to the S1 state. The significant changes of the hydrogen bond from the calculated bond lengths in different electronic states can be observed. In addition, the spectral shifts of the stretching vibrational mode of the hydrogen-bonded O–H group in different electronic states are accounted for the hydrogen bond changes in the S1 state too.