Revealing and Tuning the Photophysics of C=N Containing Photothermal Molecules: Excited State Dynamics Simulations.
Int J Mol Sci
; 23(19)2022 Oct 04.
Article
in En
| MEDLINE
| ID: mdl-36233082
ABSTRACT
Molecular photothermal conversion materials are recently attracting increasing attention for phototherapy applications. Herein we investigate the excitation and de-excitation processes of a photothermal molecule (C1TI) that is among the recently developed class of small-molecule-based photothermal imines with superb photothermal conversion efficiencies (PTCEs) up to 90% and a molecule (M2) that is constructed by replacing the amino group of C1TI with an H atom, via excited-state dynamics simulations based on the time-dependent density functional theory (TD-DFT). The simulations reveal fast (<150 fs of average time) nonradiative decays of the lowest excited singlet (S1) state to a conical intersection (CI) with the ground (S0) state in high yields (C1TI 93.9% and M2 87.1%). The fast decays, driven by C=N bond rotation to a perpendicular structural configuration, are found to be barrierless. The slight structural difference between C1TI and M2 leads to drastically different S0-S1 energy surfaces, especially M2 features a relatively much lower CI (0.8 eV in energy) and much more decay energy (1.0 eV) to approach the CI. This work provides insights into the de-excitation mechanisms and the performance tuning of C=N enabled photothermal materials.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Imines
Language:
En
Journal:
Int J Mol Sci
Year:
2022
Document type:
Article
Affiliation country:
China
Country of publication:
CH
/
SUIZA
/
SUÍÇA
/
SWITZERLAND