Experimental and theoretical study of the exited state of aminostyryl terpyridine derivatives: Hydrogen-bonding effects

- The first excited state of dimethyl/phenylamino substituted aminostyryl terpyridine derivatives exhibit ICT character in both polar aprotic and protic solvents.
- The twisting process of the dimethyl/phenylamino with respect to the stilbene group is the main relaxation process in the ICT state.
- The energy degradation via the intermolecular hydrogen bond stretching vibrations in the deactivation process along with the conformational relaxation processes can be indicative. This is consisted with the low fluorescent quantum yields for dimethyl substituted aminostyryl terpyridine in protic solvents.
- The theoretical study on conformational evolution between the ground state and excited-state can not only enrich our knowledge on the excited-state conformational study, but also help to explain the HB-influenced fluorescent emission behavior.