Novel infrared spectra for intermolecular dihydrogen bonding of the phenol-borane-trimethylamine complex in electronically excited state

The intermolecular dihydrogen bonding in the electronically excited states of the dihydrogen-bonded phenol-BTMA complex in gas phase was theoretically investigated using the time-dependent density functional theory method for the first time. It was theoretically demonstrated that the S 1 state of th...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of chemical physics 2007-07, Vol.127 (2), p.024306-024306-6
Main Authors: Zhao, Guang-Jiu, Han, Ke-Li
Format: Article
Language:English
Subjects:
Absorption
Boranes - chemistry
Chemistry, Physical - methods
Electronics
Hydrogen Bonding
Methylamines - chemistry
Models, Theoretical
Molecular Conformation
Phenol - chemistry
Spectrophotometry, Infrared - methods
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The intermolecular dihydrogen bonding in the electronically excited states of the dihydrogen-bonded phenol-BTMA complex in gas phase was theoretically investigated using the time-dependent density functional theory method for the first time. It was theoretically demonstrated that the S 1 state of the dihydrogen-bonded phenol-BTMA complex is a locally excited state, in which only the phenol moiety is electronically excited. The infrared spectra of the dihydrogen-bonded phenol-BTMA complex in ground state and the S 1 state were calculated at both the O-H and B-H stretching vibrational regions. A novel infrared spectrum of the dihydrogen-bonded phenol-BTMA complex in the electronically excited state was found. The stretching vibrational absorption bands of the dihydrogen-bonded O-H and B-H groups are very strong in the ground state, while they are disappeared in the S 1 state. At the same time, a new strong absorption band appears at the C  O stretching region. From the calculated bond lengths, it was found that both the O-H and B-H bonds in the dihydrogen bond O-H⋯H-B are significantly lengthened in the S 1 state of the dihydrogen-bonded phenol-BTMA complex. However, the C-O bond in the phenol moiety is markedly shortened in the excited state, and then has the characteristics of C  O group. Furthermore, it was demonstrated that the intermolecular dihydrogen bonds in the electronically excited state of the dihydrogen-bonded phenol-BTMA complex are strengthened, since calculated H⋯H distance is drastically shortened in the S 1 state.
ISSN:0021-9606
1089-7690
DOI:10.1063/1.2752808