Premium
Hydrogen bonding and excited state properties of the photoexcited hydrogen‐bonded ( E )‐ S ‐(2‐aminopropyl) 3‐(4‐hydroxyphenyl)prop‐2‐enethioate complexes
Author(s) -
Yang Dapeng,
Zheng Rui,
Lv Jian
Publication year - 2017
Publication title -
journal of physical organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.325
H-Index - 66
eISSN - 1099-1395
pISSN - 0894-3230
DOI - 10.1002/poc.3634
Subject(s) - time dependent density functional theory , excited state , chemistry , density functional theory , molecular orbital , hydrogen bond , homo/lumo , intermolecular force , ground state , atomic physics , molecule , photochemistry , computational chemistry , physics , organic chemistry
Abstract The time‐dependent density functional theory (TDDFT) method has been performed to investigate the excited state and hydrogen bonding dynamics of a series of photoinduced hydrogen‐bonded complexes formed by ( E )‐ S ‐(2‐aminopropyl) 3‐(4‐hydroxyphenyl)prop‐2‐enethioate with water molecules in vacuum. The ground state geometric optimizations and electronic transition energies as well as corresponding oscillator strengths of the low‐lying electronic excited states of the ( E )‐ S ‐(2‐aminopropyl) 3‐(4‐hydroxyphenyl)prop‐2‐enethioate monomer and its hydrogen‐bonded complexes O 1 ‐H 2 O, O 2 ‐H 2 O, and O 1 O 2 ‐(H 2 O) 2 were calculated by the density functional theory and TDDFT methods, respectively. It is found that in the excited states S 1 and S 2 , the intermolecular hydrogen bond formed with carbonyl oxygen is strengthened and induces an excitation energy redshift, whereas the hydrogen bond formed with phenolate oxygen is weakened and results in an excitation energy blueshift. This can be confirmed based on the excited state geometric optimizations by the TDDFT method. Furthermore, the frontier molecular orbital analysis reveals that the states with the maximum oscillator strength are mainly contributed by the orbital transition from the highest occupied molecular orbital to the lowest unoccupied molecular orbital. These states are of locally excited character, and they correspond to single‐bond isomerization while the double bond remains unchanged in vacuum.