New insights into the solvent-assisted excited-state double proton transfer of 2-(1H-pyrazol-5-yl)pyridine with alcoholic partners: A TDDFT investigation

A DFT/TDDFT investigation of the excited state proton transfer reaction of fisetin chromophore

“…The geometric optimizations of fisetin-enol, fisetin-open and fisetin-enol were performed using DFT in the S 0 state and using TDDFT in the S 1 state. Especially, the TDDFT method has become a very useful tool to theoretically investigate the hydrogen bonding interaction that occurs in the excited-state of hydrogen-bonded systems [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]. In addition, Becke's three-parameter hybrid exchange functional with Lee-Yang-Parr gradient-corrected correlation (B3LYP functional) was selected in both the DFT and TDDFT methods [69][70][71][72].…”

“…Considering the consistent with previous experiment [65], ACN has been selected as the reaction solvent in the IEFPCM model. Furthermore, the hydrogen bond strengthening or weakening could also be revealed based on monitoring the spectral shifts of vibrational modes involved in the formation of hydrogen bonds [10][11][12][13][14][15][16][17][18][38][39][40][41][42][43][44][45][46]. The vibrational spectra of fisetin-enol chromophore in the conjunct vibrational regions of the O 1 -H 2 stretching modes have been shown in Fig.…”

“…Up to now, many different sensing mechanisms, such as intramolecular charge transfer (ICT), photo-induced electron transfer (PET), fluorescence resonance energy transfer (FRET), and excited state proton transfer (ESPT) and so forth [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38], are relevant with hydrogen bonding. Particularly, the excited state interand intra-molecular proton transfer (ESIPT) reactions have been drawing great attention due to their unique photo-physical and photo-chemical properties.…”

Insight into the excited-state intramolecular double-proton transfer of the 2,5-bis(benzoxazol-2-yl)thiophene-3,4-diol: one-step or stepwise mechanism?

“…important role in the excited-state behavior of molecules, such as the photo-induced DNA mutation [48], the catalytic reactivity of enzymes [49] and the fluorescence of green fluorescent protein [50]. However, the biological molecules are huge and complex, which restricts their study and simulation, and hence, some small molecules are used as models in relevant studies.…”

The investigation of excited state proton transfer mechanism in water-bridged 7-azaindole

“…With the significant function of hydrogen bonds in chemistry, physics and biology has been identified, the proton transfer along hydrogen bond has been given more and more attention in recent years [26][27][28][29][30]. Liu [28].…”